Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion should be read in conjunction with the financial statements contained in this Form 10-Q, as well as Management’s Discussion and Analysis of Financial Condition and Results of Operations and Risk Factors contained in the Form 10-K. We intend for this discussion to provide the reader with information that will assist in understanding our financial statements, the changes in certain key items in those financial statements, and the primary factors that accounted for those changes, as well as how certain accounting principles affect our financial statements. The discussion also provides information about the financial results of our business segments to provide a better understanding of how those segments and their results affect the financial condition and results of operations of Ameren as a whole. Also see the Glossary of Terms and Abbreviations at the front of this report and in the Form 10-K.

Ameren, headquartered in St. Louis, Missouri, is a public utility holding company whose primary assets are its equity interests in its subsidiaries. Ameren’s subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. Dividends on Ameren’s common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Ameren’s principal subsidiaries are listed below. Ameren also has other subsidiaries that conduct other activities, such as providing shared services.

• Ameren Missouri operates a rate-regulated electric generation, transmission, and distribution business and a rate-regulated natural gas distribution business in Missouri.

• Ameren Illinois operates rate-regulated electric transmission, electric distribution, and natural gas distribution businesses in Illinois.

• ATXI operates a FERC rate-regulated electric transmission business within the MISO.

Ameren’s and Ameren Missouri’s financial statements are prepared on a consolidated basis and therefore include the accounts of their majority-owned subsidiaries. All intercompany transactions have been eliminated. Ameren Missouri’s subsidiaries were created for the ownership of renewable generation projects. Ameren Illinois has no subsidiaries. All tabular dollar amounts are in millions, unless otherwise indicated.

In addition to presenting results of operations and earnings amounts in total, we present certain information in cents per share. These amounts reflect factors that directly affect Ameren’s earnings. We believe this per share information helps readers to understand the impact of these factors on Ameren’s earnings per share.

OVERVIEW

Net income attributable to Ameren common shareholders in the three months ended September 30, 2024, was $456 million, or $1.70 per diluted share, compared with $493 million, or $1.87 per diluted share, in the year-ago period. Net income attributable to Ameren common shareholders in the nine months ended September 30, 2024, was $975 million, or $3.65 per diluted share, compared with $994 million, or $3.78 per diluted share, in the year-ago period. Earnings for the three and nine months ended September 30, 2024, were unfavorably affected by increased other operations and maintenance expenses not subject to formula rates, riders, or trackers, due to a charge recorded by Ameren Missouri related to an agreement in principle with the United States Department of Justice, which, if approved, would resolve all outstanding claims in the NSR and Clean Air Act litigation related to the Rush Island Energy Center. Earnings in the three and nine months ended September 30, 2024, were also unfavorably affected by increased financing costs due to higher long-term debt balances and interest rates, a lower recognized ROE under the MYRP, lower Ameren Transmission earnings resulting from the October 2024 FERC order lowering the allowed base ROE, and an increase in the weighted-average basic common shares outstanding, which reduced earnings per diluted

share. Net income for the three and nine months ended September 30, 2024, was favorably affected by increased rate base investments at Ameren Transmission and increased deferral of financing costs associated with rate base investments at Ameren Missouri. Net income for the nine months ended September 30, 2024, was favorably affected by increased base rate revenues pursuant to the MoPSC's June 2023 electric rate order and increased retail electric sales volumes at Ameren Missouri. Earnings for the nine months ended September 30, 2024, were also favorably affected by higher base rate revenues pursuant to the ICC's November 2023 natural gas rate order, which increased earnings at Ameren Illinois Natural Gas. Net income for the three months ended September 30, 2024, was unfavorably affected by decreased retail electric sales volumes at Ameren Missouri, primarily due to milder summer temperatures in 2024. Earnings for the three months ended September 30, 2024, were favorably affected by decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, primarily at Ameren Missouri and Ameren Illinois Natural Gas, excluding a charge related to an increase in the cost of additional mitigation relief discussed above, largely due to lower storm costs, an increase in the cash surrender value of COLI, and disciplined cost management including lower labor costs from decreased headcount, decreased use of contractors, and lower amortization of refueling costs for the Callaway Energy Center.

Ameren’s strategic plan includes investing in rate-regulated energy infrastructure, enhancing regulatory frameworks and advocating for responsible policies, and optimizing operating performance to capitalize on opportunities to benefit our customers, communities, shareholders, and the environment. Ameren remains focused on disciplined cost management and strategic capital allocation. Ameren invested $3.0 billion in its rate-regulated businesses in the nine months ended September 30, 2024.

In June 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for electric service by $446 million. The electric rate increase request is based on a 10.25% ROE, a capital structure composed of 52% common equity, a rate base of $14 billion, and a test year ended March 31, 2024, with certain pro-forma adjustments expected through an anticipated true-up date of December 31, 2024. The MoPSC proceeding relating to the proposed electric service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by May 2025 and new rates effective by June 2025.

In June 2024, the MoPSC issued a financing order authorizing the issuance of securitized utility tariff bonds by a wholly owned, special purpose subsidiary of Ameren Missouri to finance approximately $470 million of costs related to the planned accelerated retirement of the Rush Island Energy Center, which includes the expected remaining unrecovered net plant balance associated with the facility, among other costs. Ameren Missouri will collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance. The financing order also includes a determination that the decision to retire the Rush Island Energy Center was reasonable and prudent. The MoPSC did not make a determination regarding the prudency of Ameren Missouri's prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation discussed in Note 9 – Commitments and Contingencies under Part I, Item 1, of this report. However, claims regarding such actions could be considered in future regulatory proceedings. If future regulatory proceedings result in revenue reductions based on Ameren Missouri’s prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation, it could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri. In September 2024, the financing order became final and unappealable.

In September 2023, the United States District Court for the Eastern District of Missouri granted Ameren Missouri’s request to modify a September 2019 remedy order issued by the district court in order to allow the retirement of the Rush Island Energy Center in advance of its previously expected retirement date of 2039, in lieu of installing a flue gas desulfurization system. Ameren Missouri retired the Rush Island Energy Center on October 15, 2024. The United States Department of Justice is seeking an order from the district court providing for additional mitigation relief related to prior emissions. In November 2024, Ameren Missouri and the United States Department of Justice reached an agreement in principle, which, if approved by the district court, would resolve all outstanding claims in this case and would require Ameren Missouri to fund a program to provide electric buses and charging stations to schools in the metro St. Louis area and a program to provide air purifiers to eligible Ameren Missouri electric residential customers. These programs are estimated to cost approximately $64 million. As of September 30, 2024, Ameren and Ameren Missouri recorded liabilities of $64 million and charges of $15 million and $44 million in the first and third quarters of 2024, respectively, related to the cost of these programs.

In 2024, the MoPSC issued orders approving requested CCNs for the Split Rail, Vandalia, Bowling Green, and Cass County solar projects. Ameren Missouri acquired the Cass County, Boomtown, and Huck Finn solar projects in June 2024, September 2024, and October 2024, respectively. These three acquisitions collectively represent a purchase price of approximately $0.9 billion. In October 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement filed by Ameren Missouri, the MoPSC staff, and other intervenors requesting a CCN for the Castle Bluff Natural Gas Project. The order also includes the use of a post-construction cost deferral related to the project, which allows Ameren Missouri to defer and recover depreciation expense, financing costs, and applicable income taxes incurred from the date the project is placed in service to the date when project costs are reflected in updated base rates as a result of a regulatory rate review. The period of deferral would be limited to the earlier of the time the project costs are reflected in base rates or six months.

In February 2024, Ameren Missouri filed an update to its Smart Energy Plan with the MoPSC, which includes a five-year capital investment overview with a detailed one-year plan for 2024. The plan is designed to upgrade Ameren Missouri’s electric infrastructure and includes investments that will upgrade the grid and accommodate more renewable energy. Investments under the plan are expected to total approximately $12.4 billion over the five-year period from 2024 through 2028, with expenditures largely recoverable under the PISA. Ameren Missouri’s Smart Energy Plan excludes investments in its natural gas distribution business, as well as removal costs, net of salvage.

In January 2024, Ameren Missouri filed a proposed customer energy-efficiency plan with the MoPSC under the MEEIA. In October 2024, Ameren Missouri, the MoOPC, and other intervenors filed a nonunanimous stipulation and agreement with the MoPSC for a three-year plan, which includes a portfolio of customer energy-efficiency and demand response programs, along with the continued use of the MEEIA rider, which allows Ameren Missouri to collect from customers its actual MEEIA program costs and related lost electric revenues. If the agreement is approved, Ameren Missouri intends to invest $51 million annually in 2025 and 2026 and $22 million in 2027 in the proposed customer energy-efficiency and demand response programs. In addition, the agreement requested performance incentives applicable to each plan year to earn revenues by achieving certain spending and demand response goals. If 100% of the goals are achieved in 2025, 2026, and 2027, Ameren Missouri would earn performance incentive revenues of $5 million, $5 million, and $2 million, respectively. Ameren Missouri expects a decision by the MoPSC in the fourth quarter of 2024, but cannot predict the ultimate outcome of this regulatory proceeding.

In September 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for natural gas delivery service by $40 million. The natural gas rate increase request is based on a 10.25% ROE, a capital structure composed of 52% common equity, a rate base of $531 million, and a test year ended March 31, 2024, with certain pro-forma adjustments expected through the true-up date of December 31, 2024. The MoPSC proceeding relating to the proposed natural gas delivery service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by August 2025 and new rates effective by September 2025.

In April 2024, Ameren Illinois filed for a reconciliation adjustment to its 2023 electric distribution service revenue requirement with the ICC. In July 2024, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $158 million. The reconciliation adjustment reflects a capital structure composed of 50% common equity and Ameren Illinois’ actual 2023 recoverable costs and year-end rate base. In August 2024, the ICC staff submitted its calculation of the reconciliation adjustment, recommending approval of Ameren Illinois’ request. An ICC decision in this proceeding is required by December 2024, and any approved adjustment would be collected from customers in 2025. This is the final revenue requirement reconciliation under the IEIMA formula framework.

In December 2023, the ICC issued an order in Ameren Illinois' MYRP proceeding approving base rates for electric distribution services for 2024 through 2027 and rejecting Ameren Illinois' Grid Plan, which was addressed as part of the MYRP proceeding. Rate changes consistent with the December 2023 order became effective in January 2024 and remained effective through late June 2024, when new rates became effective pursuant to the June 2024 ICC rehearing order discussed below. The December 2023 order adopted an alternative methodology to establish a rate base and revenue requirements for the years 2024 through 2027 using Ameren Illinois’ previously approved 2022 year-end rate base. In January 2024, the ICC partially denied a rehearing requested by Ameren Illinois to revise the allowed ROE in the December 2023 order and granted Ameren Illinois’ rehearing request to reconsider the rate base for each year of the MYRP and to include a base level of investments to maintain grid reliability in each year of the MYRP. In June 2024, the ICC issued an order on Ameren Illinois’ rehearing request, approving revenue requirements for electric distribution services for 2024, 2025, 2026, and 2027 of $1,196 million, $1,282 million, $1,350 million, and $1,397 million, respectively. New rates became effective in late June 2024. In July 2024, Ameren Illinois filed a request for rehearing of the ICC’s June 2024 rehearing order to include an asset associated with other postretirement benefits in the rate base. Subsequently, in August 2024, the ICC denied the rehearing request. Also, in January 2024, Ameren Illinois filed an appeal of the December 2023 ICC order, including the 8.72% ROE, and subsequently updated the appeal filing in September 2024 to include the June 2024 rehearing order regarding the inclusion of an asset associated with other postretirement benefits in the rate base to the Illinois Appellate Court for the Fifth Judicial District. The court is under no deadline to address the appeal. In September 2024, Ameren Illinois filed an update to its revised Grid Plan and a request to update the associated MYRP revenue requirements for 2024, 2025, 2026, and 2027 of $1,215 million, $1,299 million, $1,385 million, and $1,444 million, respectively. An ICC decision on the revised Grid Plan and updated revenue requirements is expected in December 2024 with rates effective in January 2025. Ameren Illinois cannot predict the ultimate outcome of the appeal to the Illinois Appellate Court for the Fifth Judicial District, its revised Grid Plan filing, or its request to update the associated MYRP revenue requirements for 2024 through 2027.

In November 2023, the ICC issued an order in Ameren Illinois’ January 2023 natural gas delivery service regulatory rate review, which resulted in an increase to its annual revenues for natural gas delivery service of $112 million based on a 9.44% allowed ROE, a capital structure composed of 50% common equity, and a rate base of approximately $2.85 billion. The order reflected a reduction of approximately $93 million of planned distribution and transmission capital investments included in Ameren Illinois’ requested revenue increase, which used a 2024 future test year. The new rates became effective on November 28, 2023. In December 2023, Ameren Illinois filed a request for rehearing of the ICC’s November 2023 order. The filing requested the ICC revise the order to include an allowed ROE of at least 9.89%, a capital structure composed of 52% common equity, and the reversal of the approximately $93 million reduction of planned distribution and transmission capital investments included in the order, among other things. In January 2024, the ICC denied Ameren Illinois’ rehearing request. Subsequently, in January 2024, Ameren Illinois filed an appeal of the November 2023 ICC order to the Illinois Appellate Court for the Fifth Judicial District. The court is under no deadline to address the appeal. Ameren Illinois cannot predict the ultimate outcome of this appeal.

In May 2024, Ameren Illinois filed its annual electric energy-efficiency formula rate update to increase its rates by $26 million with the ICC. In September 2024, the ICC staff filed a recommendation supporting Ameren Illinois’ requested increase. An ICC decision in this proceeding is required by December 2024, with new rates effective January 2025.

In October 2024, the FERC issued an order, which decreased the allowed base ROE for FERC-regulated transmission rate base under the MISO tariff from 10.02% to 9.98% and required refunds, with interest, for the periods from November 2013 to February 2015 and from late September 2016 forward. As a result, Ameren and Ameren Illinois recognized reductions to electric revenues of $10 million and $7 million, respectively, and recognized interest expense of $2 million and $1 million, respectively, on their statements of income during the third quarter of 2024. As of September 30, 2024, Ameren and Ameren Illinois had recorded current regulatory liabilities on their balance sheets of $12 million and $8 million, respectively, to reflect the expected refunds, including interest, associated with the allowed base ROE set by the October 2024 order. The decrease in the FERC-allowed base ROE resulting from the October 2024 order is not material to Ameren Missouri’s results of operations, financial position, or liquidity.

In 2021, the MISO issued a report outlining a preliminary long-range transmission planning roadmap of projects through 2039, which considers the rapidly changing generation mix within MISO resulting from significant additions of renewable generation, actual and expected generation plant closures, and state mandates or goals for clean energy or carbon emissions reductions. In July 2022, the MISO approved the first tranche of projects under the roadmap. A portion of these projects were assigned to various utilities, of which Ameren was awarded projects that are estimated to cost approximately $1.8 billion, based on the MISO’s cost estimate. Related to these projects, Ameren began substation upgrades in May 2024 in advance of transmission line construction, which is expected to begin in 2026, with forecasted completion dates near the end of this decade. In addition, the MISO awarded two competitive bid projects to ATXI in the fourth quarter of 2023 and one in April 2024 that represent a total estimated investment of approximately $220 million for ATXI. In February 2024, Ameren Illinois and ATXI filed a request for a CCN, among other things, with the ICC related to the portion of the MISO long-range transmission projects they will construct within the ICC’s jurisdiction. A decision by the ICC is expected by mid-2025. In July 2024, ATXI filed a request for a CCN, among other things, with the MoPSC related to a portion of the MISO long-range transmission projects that it expects to construct within the MoPSC’s jurisdiction. A decision by the MoPSC is expected by mid-2025. In September 2024, the MISO revised a proposed first set of second tranche projects with estimated costs of $21.8 billion, which includes projects located in our service territories of $3.6 billion, based on the MISO’s cost estimate. The MISO is expected to approve this set of projects by the end of 2024. The MISO expects to begin developing an additional set of second tranche projects in 2025.

For further information on the matters discussed above, see Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report, and the Outlook section below.

RESULTS OF OPERATIONS

Our results of operations and financial position are affected by many factors. Economic conditions, energy-efficiency investments by our customers and by us, technological advances, distributed generation, and the actions of key customers can significantly affect the demand for our services. Ameren and Ameren Missouri results are also affected by seasonal fluctuations in winter heating and summer cooling demands and by weather conditions, such as storms, as well as by energy center maintenance outages. Additionally, fluctuations in interest rates and conditions in the capital and credit markets affect our cost of borrowing, our pension and postretirement benefits costs, the cash surrender value of COLI, and the asset value of Ameren Missouri’s nuclear decommissioning trust fund. Almost all of Ameren’s revenues are subject to state or federal regulation. This regulation has a material impact on the rates we charge customers for our services. Our results of operations, financial position, and liquidity are affected by our ability to align our overall spending, both operating and capital, with the frameworks established by our regulators. See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report and Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K for additional information regarding Ameren Missouri’s, Ameren Illinois’, and ATXI’s regulatory mechanisms.

Although the pace of inflation has slowed recently, we are still observing elevated inflation levels that continue to put pressure on the prices of labor, services, materials, and supplies, as well as elevated interest rates. Ameren Missouri and Ameren Illinois are generally allowed to pass on to customers prudently incurred costs for fuel, purchased power, and natural gas supply. Additionally, for certain non-commodity cost changes, the use of trackers, riders, formula ratemaking, and future test years, as applicable, mitigates our exposure.

Ameren Missouri principally uses coal and enriched uranium for fuel in its electric generation operations and purchases natural gas for its customers. Ameren Illinois purchases power and natural gas for its customers. The prices for these commodities can fluctuate significantly because of the global economic and political environment, weather, supply, demand, and many other factors. We have natural gas cost recovery mechanisms for our Illinois and Missouri natural gas distribution businesses, a purchased power cost recovery mechanism for Ameren Illinois’ electric distribution business, and a FAC for Ameren Missouri’s electric business.

We employ various risk management strategies to reduce our exposure to commodity risk and other risks inherent in our business. The reliability of Ameren Missouri’s energy centers and our transmission and distribution systems, and the level and timing of operations and maintenance costs and capital investment, are key factors that we seek to manage in order to optimize our results of operations, financial position, and liquidity.

Earnings Summary

The following table presents a summary of Ameren’s earnings for the three and nine months ended September 30, 2024 and 2023:

			Three Months												Nine Months
			2024						2023						2024						2023
Net income attributable to Ameren common shareholders			$	456					$	493					$	975					$	994
Earnings per common share – diluted			1.70						1.87						3.65						3.78

Net income attributable to Ameren common shareholders decreased $37 million and earnings per diluted share decreased 17 cents in the three months ended September 30, 2024, compared with the year-ago period. The decrease was due to net income decreases of $30 million and $10 million at Ameren Missouri and Ameren Illinois Electric Distribution, respectively, and an increase in net loss of $5 million at Ameren Illinois Natural Gas. These decreases were partially offset by a net income increase of $4 million at Ameren Transmission and a decrease in net loss of $4 million for activity not reported as part of a segment, primarily at Ameren (parent).

Net income attributable to Ameren common shareholders decreased $19 million and earnings per diluted share decreased 13 cents in the nine months ended September 30, 2024, compared with the year-ago period. The decrease was due to net income decreases of $20 million and $7 million at Ameren Illinois Electric Distribution and Ameren Missouri, respectively, and an increase in net loss of $13 million for activity not reported as part of a segment, primarily at Ameren (parent). These decreases were partially offset by net income increases of $12 million and $9 million at Ameren Transmission and Ameren Illinois Natural Gas.

Earnings per diluted share were unfavorably affected in the three and nine months ended September 30, 2024, compared to the year-ago periods (except where a specific period is referenced), by:

• a charge recorded by Ameren Missouri, included in other operation and maintenance expenses, related to an agreement in principle with the United States Department of Justice, which, if approved, would resolve all outstanding claims in the NSR and Clean Air Act litigation related to the Rush Island Energy Center, see Note 9 - Commitments and Contingencies under Part 1, Item 1, of this report for more information (13 cents and 17 cents per share, respectively);

• increased financing costs primarily at Ameren Missouri and Ameren (parent), largely due to higher long-term debt balances and interest rates, partially offset by lower levels of short-term borrowings (5 cents and 12 cents per share, respectively);

• lower revenue at Ameren Illinois Electric Distribution due to a lower recognized ROE under the MYRP (3 cents and 7 cents per share, respectively);

• increased weighted-average basic common shares outstanding resulting from issuances of common shares (3 cents and 6 cents per share, respectively);

• the result of the October 2024 FERC order reducing the allowed base ROE for FERC regulated transmission rate base under the MISO tariff, which decreased Ameren Transmission earnings (4 cents per share for both periods);

• decreased retail electric sales volumes at Ameren Missouri, primarily due to milder summer temperatures, partially offset by increased retail electric sales volumes, excluding the estimated effects of weather and customer energy-efficiency programs (estimated at 3 cents for the three months ended September 30, 2024);

• increased taxes other than income taxes at Ameren Missouri, largely resulting from the absence in 2024 of employee retention tax credits received under the Coronavirus Aid, Relief, and Economic Security Act (1 cent and 2 cents per share, respectively); and

• absence of recovery of previously incurred expenses at Ameren Illinois Electric Distribution (2 cents per share for the nine months ended September 30, 2024).

Earnings per diluted share were favorably affected in the three and nine months ended September 30, 2024, compared to the year-ago periods (except where a specific period is referenced), by:

*•*increased rate base investments at Ameren Transmission, which increased earnings in this segment (5 cents and 12 cents per share, respectively);

*•*increased allowance for equity funds used during construction and increased base rate revenues for the inclusion of previously deferred PISA and RESRAM interest charges pursuant to the June 2023 MoPSC electric rate order effective July 9, 2023, partially offset by increased interest charges resulting from lower deferrals in the nine months ended September 30, 2024, related to infrastructure investments associated with the PISA and RESRAM, at Ameren Missouri (5 cents and 11 cents per share, respectively);

*•*increased base rate revenues at Ameren Missouri effective July 9, 2023, pursuant to the June 2023 MoPSC electric rate order, partially offset by the net effect of amortization of previously deferred depreciation expense under the PISA and RESRAM, financing costs otherwise recoverable under the PISA and RESRAM, a lower base level of expenses included in trackers, and the net recovery for amounts associated with the reduction in sales volumes resulting from MEEIA programs (9 cents per share for the nine months ended September 30, 2024);

• decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, excluding a charge related to the NSR and Clean Air Act litigation discussed above, primarily at Ameren Missouri and Ameren Illinois Natural Gas, largely because of lower storm costs, an increase in the cash surrender value of COLI, and disciplined cost management including lower labor costs from decreased headcount, decreased use of contractors, and lower amortization of refueling costs for the Callaway Energy Center (7 cents and 1 cent per share, respectively);

• increased retail electric sales volumes at Ameren Missouri, primarily due to higher sales excluding customer energy-efficiency programs (estimated at 5 cents per share for the nine months ended September 30, 2024); and

• increased base rate revenues at Ameren Illinois Natural Gas effective November 28, 2023, pursuant to the November 2023 ICC natural gas rate order, partially offset by increased depreciation and amortization expenses included in base rates (4 cents per share for the nine months ended September 30, 2024).

The cents per share variances above are presented based on the weighted-average basic common shares outstanding in the three and nine months ended September 30, 2023, and do not reflect the impact of dilution on earnings per share, unless otherwise noted. The amounts above other than variances related to income taxes have been presented net of income taxes using Ameren’s 2024 blended federal and state statutory tax rate of 26%. For additional details regarding the Ameren Companies’ results of operations, including explanations of Operating Revenues for both Electric Revenues and Natural Gas Revenues; Fuel and Purchased Power Expenses; Other Operations and Maintenance Expenses; Depreciation and Amortization Expenses; Taxes Other Than Income Taxes; Other Income, Net; Interest Charges; and Income Taxes, see the major headings below.

Below is Ameren’s table of income statement components by segment for the three and nine months ended September 30, 2024 and 2023:

			Ameren Missouri						Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Transmission						Other / Intersegment Eliminations						Ameren
Three Months 2024:
Electric revenues			$	1,324					$	552					$	—					$	210					$	(51)					$	2,035
Natural gas revenues			18						—						121						—						(1)						138
Fuel and purchased power			(334)						(204)						—						—						39						(499)
Natural gas purchased for resale			(4)						—						(26)						—						—						(30)
Other operations and maintenance expenses			(288)						(163)						(51)						(19)						1						(520)
Depreciation and amortization expenses			(220)						(92)						(32)						(42)						(2)						(388)
Taxes other than income taxes			(109)						(21)						(14)						(2)						(4)						(150)
Operating income (loss)			387						72						(2)						147						(18)						586
Other income, net			51						23						6						8						13						101
Interest charges			(62)						(25)						(16)						(31)						(39)						(173)
Income (taxes) benefit			6						(14)						2						(34)						(17)						(57)
Net income (loss)			382						56						(10)						90						(61)						457
Noncontrolling interests – preferred stock dividends			(1)						—						—						—						—						(1)
Net income (loss) attributable to Ameren common shareholders			$	381					$	56					$	(10)					$	90					$	(61)					$	456
Three Months 2023:
Electric revenues			$	1,219					$	558					$	—					$	188					$	(44)					$	1,921
Natural gas revenues			18						—						122						—						(1)						139
Fuel and purchased power			(233)						(233)						—						—						36						(430)
Natural gas purchased for resale			(4)						—						(26)						—						—						(30)
Other operations and maintenance expenses			(256)						(132)						(56)						(15)						(11)						(470)
Depreciation and amortization expenses			(217)						(89)						(26)						(34)						(3)						(369)
Taxes other than income taxes			(108)						(21)						(12)						(2)						(4)						(147)
Operating income (loss)			419						83						2						137						(27)						614
Other income, net			44						24						8						7						18						101
Interest charges			(63)						(23)						(15)						(25)						(26)						(152)
Income (taxes) benefit			12						(18)						—						(33)						(30)						(69)
Net income (loss)			412						66						(5)						86						(65)						494
Noncontrolling interests – preferred stock dividends			(1)						—						—						—						—						(1)
Net income (loss) attributable to Ameren common shareholders			$	411					$	66					$	(5)					$	86					$	(65)					$	493

			Ameren Missouri						Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Transmission						Other / Intersegment Eliminations						Ameren
Nine Months 2024:
Electric revenues			$	2,902					$	1,567					$	—					$	586					$	(135)					$	4,920
Natural gas revenues			103						—						660						—						(1)						762
Fuel and purchased power			(689)						(564)						—						—						99						(1,154)
Natural gas purchased for resale			(41)						—						(173)						—						—						(214)
Other operations and maintenance expenses			(789)						(452)						(168)						(54)						8						(1,455)
Depreciation and amortization expenses			(623)						(278)						(98)						(121)						(5)						(1,125)
Taxes other than income taxes			(287)						(57)						(55)						(6)						(11)						(416)
Operating income (loss)			576						216						166						405						(45)						1,318
Other income, net			144						72						20						14						43						293
Interest charges			(187)						(73)						(46)						(89)						(97)						(492)
Income (taxes) benefit			4						(41)						(38)						(89)						24						(140)
Net income (loss)			537						174						102						241						(75)						979
Noncontrolling interests – preferred stock dividends			(3)						(1)						—						—						—						(4)
Net income (loss) attributable to Ameren common shareholders			$	534					$	173					$	102					$	241					$	(75)					$	975
Nine Months 2023:
Electric revenues			$	2,978					$	1,722					$	—					$	512					$	(116)					$	5,096
Natural gas revenues			123						—						665						—						(2)						786
Fuel and purchased power			(843)						(766)						—						—						91						(1,518)
Natural gas purchased for resale			(60)						—						(220)						—						—						(280)
Other operations and maintenance expenses			(732)						(394)						(173)						(44)						(25)						(1,368)
Depreciation and amortization expenses			(579)						(260)						(79)						(101)						(5)						(1,024)
Taxes other than income taxes			(276)						(57)						(48)						(6)						(11)						(398)
Operating income (loss)			611						245						145						361						(68)						1,294
Other income, net			85						74						24						21						57						261
Interest charges			(166)						(66)						(41)						(70)						(70)						(413)
Income (taxes) benefit			14						(59)						(35)						(83)						19						(144)
Net income (loss)			544						194						93						229						(62)						998
Noncontrolling interests – preferred stock dividends			(3)						(1)						—						—						—						(4)
Net income (loss) attributable to Ameren common shareholders			$	541					$	193					$	93					$	229					$	(62)					$	994

Below is Ameren Illinois’ table of income statement components by segment for the three and nine months ended September 30, 2024 and 2023:

			Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Illinois Transmission						Other / Intersegment Eliminations						Ameren Illinois
Three Months 2024:
Electric revenues			$	552					$	—					$	155					$	(35)					$	672
Natural gas revenues			—						121						—						—						121
Purchased power			(204)						—						—						35						(169)
Natural gas purchased for resale			—						(26)						—						—						(26)
Other operations and maintenance expenses			(163)						(51)						(15)						—						(229)
Depreciation and amortization expenses			(92)						(32)						(31)						—						(155)
Taxes other than income taxes			(21)						(14)						(2)						—						(37)
Operating income (loss)			72						(2)						107						—						177
Other income, net			23						6						8						—						37
Interest charges			(25)						(16)						(22)						—						(63)
Income (taxes) benefit			(14)						2						(25)						—						(37)
Net income (loss) attributable to Ameren common shareholders			$	56					$	(10)					$	68					$	—					$	114
Three Months 2023:
Electric revenues			$	558					$	—					$	136					$	(33)					$	661
Natural gas revenues			—						122						—						—						122
Purchased power			(233)						—						—						33						(200)
Natural gas purchased for resale			—						(26)						—						—						(26)
Other operations and maintenance expenses			(132)						(56)						(12)						—						(200)
Depreciation and amortization expenses			(89)						(26)						(24)						—						(139)
Taxes other than income taxes			(21)						(12)						(1)						—						(34)
Operating income			83						2						99						—						184
Other income, net			24						8						5						—						37
Interest charges			(23)						(15)						(16)						—						(54)
Income (taxes) benefit			(18)						—						(24)						—						(42)
Net income (loss) attributable to Ameren common shareholders			$	66					$	(5)					$	64					$	—					$	125
Nine Months 2024:
Electric revenues			$	1,567					$	—					$	422					$	(90)					$	1,899
Natural gas revenues			—						660						—						—						660
Purchased power			(564)						—						—						90						(474)
Natural gas purchased for resale			—						(173)						—						—						(173)
Other operations and maintenance expenses			(452)						(168)						(43)						—						(663)
Depreciation and amortization expenses			(278)						(98)						(86)						—						(462)
Taxes other than income taxes			(57)						(55)						(4)						—						(116)
Operating income			216						166						289						—						671
Other income, net			72						20						13						—						105
Interest charges			(73)						(46)						(59)						—						(178)
Income taxes			(41)						(38)						(65)						—						(144)
Net income			174						102						178						—						454
Preferred stock dividends			(1)						—						—						—						(1)
Net income attributable to common shareholder			$	173					$	102					$	178					$	—					$	453

			Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Illinois Transmission						Other / Intersegment Eliminations						Ameren Illinois
Nine Months 2023:
Electric revenues			$	1,722					$	—					$	363					$	(87)					$	1,998
Natural gas revenues			—						665						—						—						665
Purchased power			(766)						—						—						87						(679)
Natural gas purchased for resale			—						(220)						—						—						(220)
Other operations and maintenance expenses			(394)						(173)						(36)						—						(603)
Depreciation and amortization expenses			(260)						(79)						(71)						—						(410)
Taxes other than income taxes			(57)						(48)						(3)						—						(108)
Operating income			245						145						253						—						643
Other income, net			74						24						17						—						115
Interest charges			(66)						(41)						(44)						—						(151)
Income taxes			(59)						(35)						(60)						—						(154)
Net income			194						93						166						—						453
Preferred stock dividends			(1)						—						—						—						(1)
Net income attributable to common shareholder			$	193					$	93					$	166					$	—					$	452

Operating Revenues

The following table presents the increases (decreases) by Ameren segment for electric and natural gas revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods:

Three Months			Ameren Missouri						Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Transmission**(a)**						Other /Intersegment Eliminations						Ameren
Electric revenue change:
Base rates (estimate)(b)			$	2					$	8					$	—					$	18					$	—					$	28
Effect of weather (estimate)(c)			(18)						—						—						—						—						(18)
Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)			6						—						—						—						—						6
Off-system sales, capacity, and FAC revenues, net			112						—						—						—						—						112
Ameren Illinois energy-efficiency program investment revenues			—						3						—						—						—						3
Electric deferred income tax adjustment(d)			—						(9)						—						—						—						(9)
Other			4						3						—						4						(4)						7
Cost recovery mechanisms – offset in fuel and purchased power(e)			(11)						(29)						—						—						(3)						(43)
Other cost recovery mechanisms(f)			10						18						—						—						—						28
Total electric revenue change			$	105					$	(6)					$	—					$	22					$	(7)					$	114
Natural gas revenue change:
Base rates (estimate)			$	—					$	—					$	8					$	—					$	—					$	8
Change in rate design (estimate)			—						—						(9)						—						—						(9)
Total natural gas revenue change			$	—					$	—					$	(1)					$	—					$	—					$	(1)
Nine Months
Electric revenue change:
Base rates (estimate)(b)			$	62					$	24					$	—					$	63					$	—					$	149
Effect of weather (estimate)(c)			3						—						—						—						—						3
Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)			17						—						—						—						—						17
Off-system sales, capacity, and FAC revenues, net			(135)						—						—						—						—						(135)
Ameren Illinois energy-efficiency program investment revenues			—						14						—						—						—						14
Electric deferred income tax adjustment(d)			—						(18)						—						—						—						(18)
Other			3						—						—						11						(11)						3
Cost recovery mechanisms – offset in fuel and purchased power(e)			(49)						(202)						—						—						(8)						(259)
Other cost recovery mechanisms(f)			23						27						—						—						—						50
Total electric revenue change			$	(76)					$	(155)					$	—					$	74					$	(19)					$	(176)
Natural gas revenue change:
Base rates (estimate)			$	—					$	—					$	43					$	—					$	—					$	43
Change in rate design (estimate)			—						—						(3)						—						—						(3)
Effect of weather (estimate)(c)			1						—						—						—						—						1
Other			—						—						3						—						1						4
Cost recovery mechanisms – offset in natural gas purchased for resale(e)			(20)						—						(47)						—						—						(67)
Other cost recovery mechanisms(f)			(1)						—						(1)						—						—						(2)
Total natural gas revenue change			$	(20)					$	—					$	(5)					$	—					$	1					$	(24)

(a)Includes an increase in transmission revenues of $19 million and $59 million at Ameren Illinois for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods.

(b)For Ameren Illinois Electric Distribution and Ameren Transmission, base rates include increases or decreases in operating revenues related to the revenue requirement reconciliation adjustment under the MYRP and formula rates, respectively. For Ameren Missouri, base rates exclude an increase for the recovery of lost electric revenue, less the associated fuel and purchased power expenses, resulting from the MEEIA customer energy-efficiency programs and a decrease in base rates for RESRAM. These changes in Ameren Missouri base rates are included in the “Sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)” and “Cost recovery mechanisms - offset in fuel and purchased power” line items, respectively.

(c)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on electric and natural gas demand compared with the year-ago periods; this variation is based on temperature readings from National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.

(d)The electric deferred income tax adjustment relates to the remaining balance of certain excess deferred income taxes that will be amortized through 2025. Offsetting expense increases or decreases are reflected within the "Income Taxes" section of the statement of income. This item has no overall impact on earnings.

(e)Electric and natural gas revenue changes are offset by corresponding changes in “Fuel and purchased power” and “Natural gas purchased for resale” on the statement of income. For the three and nine months ended September 30, 2024, activity in Other/Intersegment Eliminations of $3 million and $8 million, respectively, represents the changes in eliminations of related-party transactions between Ameren Missouri, Ameren Illinois, and ATXI (-$1 million and -$5 million, respectively), as well as changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$2 million and -$3 million, respectively). See Note 8 – Related-party Transactions and Note 14 – Segment Information under Part I, Item 1, of this report for additional information on intersegment eliminations. These items have no overall impact on earnings.

(f)Offsetting expense increases or decreases are reflected in “Other operations and maintenance,” “Depreciation and amortization,” or in “Taxes other than income taxes,” within the “Operating Expenses” section of the statement of income. These items have no overall impact on earnings.

Electric Revenues

Ameren

Ameren’s electric revenues increased $114 million, or 6%, for the three months ended September 30, 2024, compared with the year-ago period, primarily due to increased revenues at Ameren Missouri and Ameren Transmission, partially offset by decreased revenues at Ameren Illinois Electric Distribution, as discussed below. Ameren’s electric revenues decreased $176 million, or 3%, for the nine months ended September 30, 2024, compared with the year-ago period, primarily due to decreased revenues at Ameren Illinois Electric Distribution and Ameren Missouri, partially offset by increased revenues at Ameren Transmission, as discussed below.

Ameren Transmission

Ameren Transmission’s electric revenues increased $22 million, or 12%, and $74 million, or 14%, for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods. Revenues were favorably affected by higher recoverable expenses

(+$15 million and +$40 million, respectively), increased capital investment (+$13 million and +$33 million, respectively), as evidenced by a 15% increase in rate base used to calculate the revenue requirement, and increased facility rental revenues (+$4 million and +$11 million, respectively) related to ATXI’s transmission operations control center, which was placed in service in December 2023. ATXI provides affiliates with access to this facility. Rental revenues associated with this facility are affiliate transactions and eliminated in consolidation for Ameren’s consolidated financial statements. See Note 8 – Related-party Transactions under Part I, Item 1, of this report for additional information. Revenues were unfavorably affected by a decrease in the allowed base ROE under the MISO tariff resulting from the October 2024 FERC order, which included customer refunds for certain historical periods (-$10 million and -$10 million, respectively). See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report for additional information regarding the FERC complaint cases.

Ameren Missouri

Ameren Missouri’s electric revenues increased $105 million, or 9%, for the three months ended September 30, 2024, and decreased $76 million, or 3%, for the nine months ended September 30, 2024, compared with the year-ago periods.

The following items had an unfavorable effect on Ameren Missouri’s electric revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

•“Off-system sales, capacity and FAC revenues, net” decreased $135 million for the nine months ended September 30, 2024, primarily due to lower winter and spring capacity prices, partially offset by higher summer capacity prices which were set by annual MISO auctions. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC is included within “Off-system sales, capacity, and FAC revenues, net” and “Energy costs (excluding the estimated effect of weather)” in fuel and purchased power.

• Revenues associated with “Cost recovery mechanisms – offset in fuel and purchased power” decreased $11 million and $49 million, respectively, due to decreased revenue related to the amortization of costs previously deferred under the FAC that were reflected in customer rates. The changes to “Cost recovery mechanisms - offset in fuel and purchased power” are fully offset by changes to “Cost recovery mechanisms - offset in electric revenue” in fuel and purchased power.

• The aggregate effect of weather decreased revenues an estimated $18 million for the three months ended September 30, 2024, due to milder summer temperatures as cooling degree days decreased 5%.

The following items had a favorable effect on Ameren Missouri’s electric revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

• “Off-system sales, capacity and FAC revenues, net” increased $112 million for the three months ended September 30, 2024, primarily due to higher summer capacity prices which were set by annual MISO auctions. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC is included within “Off-system sales, capacity, and FAC revenues, net” and “Energy costs (excluding the estimated effect of weather)” in fuel and purchased power.

• Higher electric base rates, resulting from the June 2023 MoPSC electric rate order effective July 9, 2023, increased revenues an estimated $2 million and $62 million, respectively.

• Revenues associated with other cost recovery mechanisms increased $10 million and $23 million, respectively, primarily due to an increase in RESRAM revenues in both periods and an increase in excise taxes due to increased retail sales revenue for the nine months ended September 30, 2024.

• Excluding the estimated effects of weather and the MEEIA customer energy-efficiency programs, electric revenues increased an estimated $6 million and $17 million, respectively, for the three and nine months ended September 30, 2024, due to an increase in retail sales volumes, which were, in part, favorably affected by the absence of customer outages resulting from major storms experienced throughout the service territory in July and August 2023 and an additional day in 2024 as a result of the leap year. The increase is partially offset by lower realized prices due to changes in customer usage patterns and economic development discounts.

• Other revenues increased by $3 million in both periods, primarily due to increased mutual assistance related to storm recovery.

• The aggregate effect of weather increased revenues an estimated $3 million for the nine months ended September 30, 2024, due to warmer spring temperatures largely offset by milder summer temperatures and warmer winter temperatures, as cooling degree days increased 6% and heating degree days decreased 6%.

Ameren Illinois

Ameren Illinois’ electric revenues increased $11 million, or 2%, for the three months ended September 30, 2024, compared with the year-ago period, driven by increased revenues at Ameren Illinois Transmission, partially offset by decreased revenues at Ameren Illinois Electric Distribution. Ameren Illinois’ electric revenues decreased $99 million, or 5%, for the nine months ended September 30, 2024, compared with the year-ago period, driven by decreased revenues at Ameren Illinois Electric Distribution, partially offset by increased revenues at Ameren Illinois Transmission.

Ameren Illinois Electric Distribution

Ameren Illinois Electric Distribution’s revenues decreased $6 million, or 1%, and $155 million, or 9%, for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods.

The following items had an unfavorable effect on Ameren Illinois Electric Distribution’s revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods:

• Revenues associated with “Cost recovery mechanisms – offset in fuel and purchased power” decreased $29 million and $202 million, respectively, due to decreased purchased power expenses recovered from customers. The decreases in electric revenues are fully offset by decreases in purchased power expenses under cost recovery mechanisms for purchased power, as discussed below.

• Pursuant to an ICC order, revenues decreased $9 million and $18 million, respectively, due to an increase in the amortization rate for certain excess deferred income taxes.

The following items had a favorable effect on Ameren Illinois Electric Distribution’s revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

*•*Other cost recovery mechanisms increased revenues by $18 million and $27 million, respectively, primarily due to a higher amount of bad debt and purchased receivables from alternative retail electric suppliers included in customer rates pursuant to their associated riders, partially offset by lower environmental remediation revenues.

• Base rates increased revenues by $8 million and $24 million, respectively, primarily due to higher recoverable non-purchased power expenses (+$16 million and +$41 million, respectively) and increased capital investment of $1 million for the nine months ended September 30, 2024, partially offset by a lower recognized ROE (-$8 million and -$18 million, respectively). The MYRP utilizes a fixed ROE approved by the ICC of 8.72%, with adjustments for any performance incentives and penalties, while the IEIMA formula-based ROE was based on the annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points (estimated at 9.80% for the nine months ended September 30, 2023).

• Revenues associated with customer energy-efficiency program investments increased $3 million and $14 million, respectively, due to the recovery of program expenses (+$3 million and +$10 million, respectively), an increase in the ROE due to maximum achievement of the annual energy savings goals in 2023 of $3 million for the nine months ended September 30, 2024, and increased investment of $1 million for the nine months ended September 30, 2024.

Ameren Illinois Transmission

Ameren Illinois Transmission’s revenues increased $19 million, or 14%, and $59 million, or 16%, for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods. Base rate revenues were favorably affected by higher recoverable expenses (+$16 million and +$41 million, respectively) and increased capital investment (+$10 million and +$25 million, respectively), as evidenced by a 16% increase in rate base used to calculate the revenue requirement. Base rate revenues were unfavorably affected by a decrease in the allowed base ROE under the MISO tariff resulting from the October 2024 FERC order, which included customer refunds for certain historical periods (-$7 million and -$7 million, respectively). See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report for additional information regarding the FERC complaint cases.

Natural Gas Revenues

Ameren

Ameren’s natural gas revenues were comparable for the three months ended September 30, 2024, and decreased $24 million, or 3%, for the nine months ended September 30, 2024, compared with the year-ago periods, due to decreased revenues at Ameren Missouri and Ameren Illinois Natural Gas, as discussed below.

Ameren Missouri

Ameren Missouri’s natural gas revenues were comparable for the three months ended September 30, 2024, and decreased $20 million, or 16%, for the nine months ended September 30, 2024, compared with the year-ago periods. Revenues associated with “Cost recovery mechanisms – offset in natural gas purchased for resale” decreased $20 million for the nine months ended September 30, 2024, due to lower commodity prices and the absence of amortization of natural gas costs deferred under the PGA related to the extremely cold weather in mid-February 2021. Changes in natural gas revenues under the PGA are fully offset by corresponding changes in natural gas purchased for resale expenses.

Ameren Illinois Natural Gas

Ameren Illinois Natural Gas’ revenues were comparable for the three months ended September 30, 2024, and decreased $5 million, or 1%, for the nine months ended September 30, 2024, compared with the year-ago periods.

The following items had an unfavorable effect on Ameren Illinois Natural Gas’ revenues for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

• “Cost recovery mechanisms – offset in natural gas purchased for resale” decreased revenues $47 million for the nine months ended September 30, 2024, due to lower collection of natural gas costs previously deferred under the PGA. Changes in natural gas revenues under the PGA are fully offset by the decrease in natural gas purchased for resale expenses.

• The implementation of a change in rate design pursuant to the November 2023 natural gas rate order decreased revenues an estimated $9 million and $3 million, respectively. This change in rate design concentrates more revenues in the winter heating season due to an increase in volumetric rates and a decrease in fixed customer rates. As such, the change is not expected to materially affect annual earnings comparisons.

The decreases in Ameren Illinois Natural Gas’ revenues were partially offset by estimated increases of $8 million and $43 million for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, due to higher natural gas base rates as a result of the November 2023 natural gas rate order.

Fuel and Purchased Power

The following table presents the increases (decreases) by Ameren segment for fuel and purchased power for the three and nine months ended September 30, 2024, compared with the year-ago periods:

Three Months			Ameren Missouri						Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Transmission						Other /Intersegment Eliminations						Ameren
Fuel and purchased power change:
Energy costs (excluding the estimated effect of weather)			$	113					$	—					$	—					$	—					$	—					$	113
Effect of weather (estimate)(a)			(2)						—						—						—						—						(2)
Effect of higher net energy costs included in base rates			1						—						—						—						—						1
Cost recovery mechanisms – offset in electric revenue(b)			(11)						(29)						—						—						(3)						(43)
Total fuel and purchased power change			$	101					$	(29)					$	—					$	—					$	(3)					$	69
Nine Months
Fuel and purchased power change:
Energy costs (excluding the estimated effect of weather)			$	(130)					$	—					$	—					$	—					$	—					$	(130)
Effect of higher net energy costs included in base rates			22						—						—						—						—						22
Other			3						—						—						—						—						3
Cost recovery mechanisms – offset in electric revenue(b)			(49)						(202)						—						—						(8)						(259)
Total fuel and purchased power change			$	(154)					$	(202)					$	—					$	—					$	(8)					$	(364)

(a)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on electric demand compared with the year-ago periods; this variation is based on temperature readings from the National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.

(b)“Cost recovery mechanisms — offset in electric revenue” changes are offset by corresponding changes in “Cost recovery mechanisms — offset in fuel and purchased power” in electric revenues. For the three and nine months ended September 30, 2024, activity in Other/Intersegment Eliminations of $3 million and $8 million, respectively, represents the changes in eliminations of related-party transactions between Ameren Missouri, Ameren Illinois, and ATXI (-$1 million and -$5 million, respectively), as well as changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$2 million and -$3 million, respectively). See Note 8 – Related-party Transactions and Note 14 – Segment Information under Part I, Item 1, of this report for additional information on intersegment eliminations. These items have no overall impact on earnings.

Ameren

Ameren Missouri and Ameren Illinois are generally allowed to pass on to customers prudently incurred costs for fuel and purchased power. Ameren’s electric fuel and purchased power expenses increased $69 million, or 16%, for the three months ended September 30, 2024, compared with the year-ago period, primarily due to increased fuel and purchased power expenses at Ameren Missouri, partially offset by decreased fuel and purchased power expenses at Ameren Illinois Electric Distribution, as discussed below. Ameren’s electric fuel and purchased power expenses decreased $364 million, or 24%, for the nine months ended September 30, 2024, compared with the year-ago period, primarily due to decreased fuel and purchased power expenses at Ameren Illinois Electric Distribution and Ameren Missouri, as discussed below.

Ameren Missouri

Ameren Missouri’s fuel and purchased power expenses increased $101 million, or 43%, for the three months ended September 30, 2024, and decreased $154 million, or 18%, for the nine months ended September 30, 2024, compared with the year-ago periods.

The following items decreased Ameren Missouri’s fuel and purchased power expense for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

• Energy costs decreased $130 million for the nine months ended September 30, 2024, primarily due to lower winter and spring capacity prices, partially offset by higher summer capacity prices, which were set by annual MISO auctions. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC is included within “Energy costs (excluding the estimated effect of weather)” and “Off-system sales, capacity, and FAC revenues, net” in electric revenues.

• “Cost recovery mechanisms — offset in electric revenue” decreased $11 million and $49 million, respectively, due to decreased amortization of costs previously deferred under the FAC. The changes to “Cost recovery mechanisms - offset in electric revenue” are fully offset by “Cost recovery mechanisms - offset in fuel and purchased power” in electric revenues.

The following items increased Ameren Missouri’s fuel and purchased power expense for the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

• Energy costs increased $113 million for the three months ended September 30, 2024, primarily due to higher summer capacity prices, which were set by annual MISO auctions. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC is included within “Energy costs (excluding the estimated effect of weather)” and “Off-system sales, capacity, and FAC revenues, net” in electric revenues.

• The effect of higher net energy costs included in base rates increased Ameren Missouri’s fuel and purchased power expenses $22 million for the nine months ended September 30, 2024, as a result of the June 2023 MoPSC electric rate order.

Ameren Illinois Electric Distribution

Ameren Illinois Electric Distribution’s purchased power expenses decreased $29 million, or 12%, and $202 million, or 26%, for the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, primarily due to decreased energy prices (-$5 million and -$83 million, respectively), which largely reflect the results of IPA procurement events, decreased capacity prices (-$8 million and -$67 million, respectively), which were set by annual MISO auctions, and lower volumes (-$14 million and -$51 million, respectively) primarily due to residential and small commercial customers switching from Ameren Illinois’ supplied power to alternative retail electric suppliers and customer adoption of solar technology through initiatives required under Illinois law. The changes to “Cost recovery mechanisms - offset in electric revenue” are fully offset by changes to “Cost recovery mechanisms - offset in fuel and purchased power” in electric revenues.

Natural Gas Purchased for Resale

The following table presents the increases (decreases) by Ameren segment for natural gas purchased for resale for the three and nine months ended September 30, 2024, compared with the year-ago periods:

Three Months			Ameren Missouri						Ameren Illinois Electric Distribution						Ameren Illinois Natural Gas						Ameren Transmission						Other /Intersegment Eliminations						Ameren
Natural gas purchased for resale change:
Effect of weather (estimate)(a)			$	(1)					$	—					$	—					$	—					$	—					$	(1)
Cost recovery mechanisms – offset in natural gas revenue(b)			1						—						—						—						—						1
Total natural gas purchased for resale change			$	—					$	—					$	—					$	—					$	—					$	—
Nine Months
Natural gas purchased for resale change:
Effect of weather (estimate)(a)			$	1					$	—					$	—					$	—					$	—					$	1
Cost recovery mechanisms – offset in natural gas revenue(b)			(20)						—						(47)						—						—						(67)
Total natural gas purchased for resale change			$	(19)					$	—					$	(47)					$	—					$	—					$	(66)

(a)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on natural gas demand compared with the year-ago periods; this variation is based on temperature readings from the National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.

(b)Natural gas purchased for resale changes are offset by corresponding changes in “Natural gas revenues” on the statement of income. These items have no overall impact on earnings.

Ameren

Ameren Missouri and Ameren Illinois are allowed to pass on to customers prudently incurred costs for natural gas purchased for resale. Ameren’s natural gas purchased for resale expenses were comparable for the three months ended September 30, 2024, and decreased $66 million, or 24%, for the nine months ended September 30, 2024, compared with the year-ago periods, due to decreased natural gas purchased for resale expenses at Ameren Illinois Natural Gas and Ameren Missouri, as discussed below.

Ameren Missouri

Ameren Missouri’s natural gas purchased for resale expenses were comparable for the three months ended September 30, 2024, and decreased $19 million, or 32%, for the nine months ended September 30, 2024, compared with the year-ago periods. Expenses associated with “Cost recovery mechanisms – offset in natural gas revenue” decreased $20 million for the nine months ended September 30, 2024, due to lower commodity prices and the absence of amortization of natural gas costs deferred under the PGA related to the extremely cold weather in mid-February 2021. Changes in natural gas purchased for resale expenses are fully offset by corresponding changes in natural gas revenues under the PGA.

Ameren Illinois Natural Gas

Ameren Illinois Natural Gas’ natural gas purchased for resale expenses were comparable for the three months ended September 30, 2024, and decreased $47 million, or 21%, for the nine months ended September 30, 2024, compared with the year-ago periods, primarily due to lower amortization of natural gas costs that were previously deferred under the PGA and lower natural gas prices. Changes in natural gas purchased for resale expenses are fully offset by changes in natural gas revenues under the PGA.

Other Operations and Maintenance Expenses

									Increase (Decrease) by Segment
									Overall Ameren Increase of $50 Million (QTD YoY)						Overall Ameren Increase of $87 Million (YTD YoY)
			Total by Segment**(a)**

(a)Includes $19 million and $15 million at Ameren Transmission in the three months ended September 30, 2024 and 2023, respectively. Includes other/intersegment eliminations of $(1) million and $11 million in the three months ended September 30, 2024 and 2023, respectively. Also includes other/intersegment eliminations of $(8) million and $25 million in the nine months ended September 30, 2024 and 2023, respectively.

						Ameren Missouri									Ameren Illinois Natural Gas									Other/Intersegment Eliminations
						Ameren Illinois Electric Distribution									Ameren Transmission

Ameren

Other operations and maintenance expenses increased $50 million and $87 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, because of the changes discussed below. In addition to changes by segments discussed below, other operations and maintenance expenses decreased $12 million and $33 million in the three and nine months ended September 30, 2024, respectively, for activity not reported as part of a segment, as reflected in “Other/Intersegment Eliminations” above, primarily because of an increase in the elimination of intercompany rent related to ATXI’s operations control center discussed below of $5 million and $10 million, respectively; a $9 million gain on the sale of land in the nine months ended September 30, 2024; and an increase in the elimination of the non-service cost component of net periodic benefit income at Ameren Services of $3 million and $8 million, respectively. The non-service cost component of net periodic benefit cost or income at Ameren Services is allocated to the segments and primarily included in the segments’ other operations and maintenance expenses.

Ameren Transmission

Other operations and maintenance expenses increased $4 million and $10 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, primarily because of increased costs related to ATXI’s operations control center, which was placed in service in December 2023. ATXI provides affiliates with access to this facility. The rent expense associated with this facility is an affiliate transaction and eliminated in consolidation for purposes of Ameren’s consolidated financial statements. See Note 8 – Related-party Transactions under Part I, Item 1, of this report for additional information.

Ameren Missouri

Other operations and maintenance expenses increased $32 million and $57 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods. The following items increased other operations and maintenance expenses in the three and nine months ended September 30, 2024, compared with the year-ago periods (except where a specific period is referenced):

• A $44 million and $59 million charge, respectively, related to an agreement in principle with the United States Department of Justice, which, if approved, would resolve all outstanding claims in the NSR and Clean Air Act litigation related to the Rush Island Energy Center, see Note 9 - Commitments and Contingencies under Part 1, Item 1, of this report for more information.

• The absence in 2024 of the recognition of regulatory assets for previously expensed costs approved for recovery pursuant to the June 2023 MoPSC rate order increased expenses $15 million for the nine months ended September 30, 2024.

• Individually insignificant increases of $2 million and $8 million, respectively, in various other operations and maintenance expenses, including other labor, cloud computing costs, and amortization of regulatory assets associated with previously expensed costs approved for recovery pursuant to the June 2023 MoPSC rate order.

• Legal and administrative expenses increased by $5 million, in the nine months ended September 30, 2024, primarily related to environmental matters.

• The absence of previously deferred expenses increased expense by $4 million in the three months ended September 30, 2024.

• Renewable development costs increased $3 million in the nine months ended September 30, 2024, primarily due to the absence in 2024 of the MoPSC order approving CCNs for the Boomtown and Huck Finn solar projects in the first half of 2023 that led to increased capitalization of renewable development costs pursuant to anticipated recovery from customers.

• Costs for injuries and damages increased $3 million in the three months ended September 30, 2024, primarily due to an increase in claims.

The above increases in the three and nine months ended September 30, 2024, compared with the year-ago periods, were partially offset by the following items (except where a specific period is referenced):

*•*Pension and benefit costs decreased $21 million in the nine months ended September 30, 2024, because of a lower base level of expenses, subject to a tracker, included in customer rates pursuant to the June 2023 MoPSC electric rate order. See Note 11 - Retirement Benefits under Part 1, Item 1 of this report for more information.

*•*Energy center maintenance decreased $3 million and $12 million, respectively, primarily because of lower amortization of Callaway Energy Center refueling and maintenance costs resulting from cost saving initiatives in the fall 2023 outage, compared to the spring 2022 outage.

• Transmission and distribution storm-related costs decreased $11 million in the three months ended September 30, 2024, because of the major storms experienced throughout the service territory in July and August 2023.

• The cash surrender value of COLI increased $7 million and $5 million, respectively, primarily because of favorable market returns in 2024 compared with unfavorable market returns in 2023.

Ameren Illinois

Other operations and maintenance expenses increased $29 million and $60 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, as discussed below.

Ameren Illinois Electric Distribution

Other operations and maintenance increased $31 million and $58 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods primarily due to the following items:

• Bad debt costs increased $19 million and $35 million, respectively, primarily because of a higher base level of expenses included in customer rates pursuant to the associated rider.

• Amortization of previous deferrals associated with bad debt costs on purchased receivables increased $5 million and $10 million, respectively, primarily because of a higher base level of expenses included in customer rates pursuant to the associated rider.

• Increased costs associated with customer energy-efficiency investments under formula ratemaking of $2 million and $8 million, respectively, primarily due to amortization of regulatory assets.

*•*Pension and benefits costs increased $6 million in both periods, primarily due to an increase in medical benefit claims related to active plan participants.

• Increased labor expense of $2 million and $5 million, respectively, primarily caused by reduced capital expenditures due to steps taken to align 2024 operations under the MYRP order, resulting in more maintenance activities.

• Costs for injuries and damages increased $2 million and $3 million, respectively, primarily because of an increase in claims.

• Absence of major storm-related cost deferrals in 2024 increased expense by $3 million in the nine months ended September 30, 2024.

• Vegetation management costs increased by $3 million in the nine months ended September 30, 2024, due to increased maintenance activity.

The above increases in the three and nine months ended September 30, 2024, compared with the year-ago periods, were partially offset by the following items:

• Reduction in environmental remediation rider costs of $4 million and $12 million, respectively.

• The cash surrender value of company-owned life insurance increased $3 million in both periods, primarily because of favorable market returns in 2024 when compared with unfavorable market returns in 2023.

Ameren Illinois Natural Gas

Other operations and maintenance costs decreased $5 million in the three and nine months ended September 30, 2024, compared with the year-ago periods, primarily due to a decrease of $4 million in contractor service costs and a $2 million decrease in labor expense due to steps taken to align operations and maintenance expense as a result of the November 2023 ICC natural gas rate order. These decreases were partially offset by an increase of $2 million in cloud computing costs.

Ameren Illinois Transmission

Other operations and maintenance expenses increased $3 million and $7 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, primarily because of increased costs related to ATXI’s operations control center, which was placed in service in December 2023. ATXI provides affiliates with access to this facility. The rent expense associated with this facility is an affiliate transaction and eliminated in consolidation for purposes of Ameren’s consolidated financial statements. See Note 8 – Related-party Transactions under Part I, Item 1, of this report for additional information.

Depreciation and Amortization Expenses

									Increase by Segment
									Overall Ameren Increase of $19 Million (QTD YoY)						Overall Ameren Increase of $101 Million (YTD YoY)
			Total by Segment**(a)**

(a)Includes other/intersegment eliminations of $2 million and $3 million in the three months ended September 30, 2024 and 2023, respectively. Also includes other/intersegment eliminations of $5 million and $5 million in the nine months ended September 30, 2024 and 2023, respectively.

						Ameren Missouri									Ameren Illinois Natural Gas									Other/Intersegment Eliminations
						Ameren Illinois Electric Distribution									Ameren Transmission

Depreciation and amortization expenses increased $19 million, $16 million, and $3 million in the three months ended September 30, 2024, and $101 million, $52 million, and $44 million in the nine months ended September 30, 2024, compared with the year-ago periods, at Ameren, Ameren Illinois, and Ameren Missouri respectively, primarily because of additional property, plant, and equipment investments across their respective segments. Ameren’s and Ameren Missouri’s depreciation and amortization expenses for the three and nine months ended September 30, 2024, compared with the year-ago periods, were affected by the following, which include the effect of the additional investments at Ameren Missouri:

• Increased depreciation and amortization of $40 million in the nine months ended September 30, 2024, due to the inclusion in base rates

of amounts previously deferred under the PISA and RESRAM effective July 9, 2023, pursuant to the June 2023 MoPSC electric rate order.

• The lower net under-recovery of RESRAM eligible expenses and increased amortization of prior deferrals increased depreciation and amortization expenses by $10 million and $28 million, respectively.

• Depreciation and amortization rate changes pursuant to the electric rate orders noted above, which increased depreciation and amortization expenses by $4 million in the nine months ended September 30, 2024.

• Depreciation and amortization expenses reflected a deferral to a regulatory asset of depreciation associated with investments in eligible property, plant, and equipment not yet included in base rates, pursuant to PISA and RESRAM. Base rates were updated to include the eligible property, plant, and equipment in-service through December 31, 2022, when new customer rates became effective on July 9, 2023, pursuant to the June 2023 MoPSC electric rate order. The effect of rebasing PISA and RESRAM, partially offset by increased amortization of prior PISA deferrals in the nine months ended September 30, 2024, decreased depreciation and amortization by $4 million and $20 million, respectively.

• The higher net deferral pursuant to a tracker related to certain excess deferred income taxes, which decreased depreciation and amortization expenses by $4 million and $8 million, respectively.

Taxes Other Than Income Taxes

									Increase by Segment
									Overall Ameren Increase of $3 Million (QTD YoY)						Overall Ameren Increase of $18 Million (YTD YoY)
			Total by Segment**(a)**

(a)Includes $2 million, $2 million, $6 million, and $6 million at Ameren Transmission in the three months ended September 30, 2024 and 2023, and in the nine months ended September 30, 2024 and 2023, respectively. Also includes other/intersegment eliminations of $4 million, $4 million, $11 million, and $11 million in the three months ended September 30, 2024 and 2023, and in the nine months ended September 30, 2024 and 2023, respectively.

						Ameren Missouri									Ameren Illinois Natural Gas									Other/Intersegment Eliminations
						Ameren Illinois Electric Distribution									Ameren Transmission

Taxes other than income taxes increased $3 million in the three months ended September 30, 2024, compared with the year-ago period, primarily because of an increase of $2 million at Ameren Illinois Natural Gas due to an increase in excise taxes resulting from higher invested capital taxes.

Taxes other than income taxes increased $18 million in the nine months ended September 30, 2024, compared with the year-ago period, primarily because of an increase of $7 million and $2 million at Ameren Missouri and Ameren Illinois Electric Distribution, respectively, because of the absence in 2024 of employee retention tax credits received under the Coronavirus Aid, Relief, and Economic Security Act; an increase of $6 million at Ameren Illinois Natural Gas due to an increase in excise taxes resulting from higher invested capital taxes; and an increase of $2 million in gross receipts taxes at Ameren Missouri, primarily due to increased retail electric sales.

Other Income, Net

									Increase (Decrease) by Segment
									Overall Ameren Change of $— Million (QTD YoY)						Overall Ameren Increase of $32 Million (YTD YoY)
			Total by Segment**(a)**

(a)Includes $8 million and $7 million at Ameren Transmission in the three months ended September 30, 2024 and 2023, respectively.

						Ameren Missouri									Ameren Illinois Natural Gas									Other/Intersegment Eliminations
						Ameren Illinois Electric Distribution									Ameren Transmission

See Note 5 – Other Income, Net, under Part I, Item 1, of this report for additional information. See Note 11 – Retirement Benefits under Part I, Item 1, of this report for more information on the non-service cost components of net periodic benefit income.

Ameren

Other income, net, was comparable in the three months ended September 30, 2024. Other income, net, increased $32 million in the nine months ended September 30, 2024. In addition to changes discussed below, other income, net, decreased $3 million and $10 million, respectively, because of increases in the non-service cost component of net periodic benefit income for activity not reported as part of a segment.

Ameren Transmission

Other income, net, was comparable in the three months ended September 30, 2024. Other income, net, decreased $7 million in the nine months ended September 30, 2024, due to lower allowance for equity funds used during construction, primarily related to lower average construction work in progress balances and an increased level of short-term borrowings included in the calculation.

Ameren Missouri

Other income, net, increased $7 million and $59 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, primarily because of an increase of $42 million in the nine months ended September 30, 2024, in the non-service cost component of net periodic benefit income because of changes in the base level of pension and postretirement costs pursuant to the June 2023 MoPSC electric rate order. Other income, net, also increased $7 million and $18 million, respectively, because of a higher allowance for equity funds used during construction resulting from higher average construction work in progress balances.

Ameren Illinois

Other income, net, was comparable at Ameren Illinois in the three months ended September 30, 2024. Other income, net, decreased $10 million in the nine months ended September 30, 2024, compared with the year-ago period, primarily because of a decrease of $9 million and $4 million in the non-service cost component of net periodic benefit income at Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas, respectively. Other income, net decreased $5 million in the allowance of equity funds used during construction, largely at Ameren Illinois Transmission. These decreases were partially offset by the increase in other interest income on regulatory balances of $8 million at Ameren Illinois Electric Distribution.

Interest Charges

									Increase by Segment
									Overall Ameren Increase of $21 Million (QTD YoY)						Overall Ameren Increase of $79 Million (YTD YoY)
			Total by Segment

						Ameren Missouri									Ameren Illinois Natural Gas									Other/Intersegment Eliminations
						Ameren Illinois Electric Distribution									Ameren Transmission

See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and the Long-term Debt and Equity section below for additional information on short-term borrowings and long-term debt, respectively, discussed below.

Ameren

Interest charges increased $21 million and $79 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods. In addition to changes by segments discussed below, interest charges increased $13 million and $27 million, respectively, compared with the year-ago periods, at Ameren (parent) primarily because of issuances of long-term debt in November and December of 2023, which collectively increased interest charges by $17 million and $52 million, respectively. The net proceeds from these issuances were used to repay short-term borrowings, which decreased short-term interest expense by $4 million and $25 million, respectively, compared with the year-ago periods.

Ameren Transmission

Interest charges increased $6 million and $19 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, because of an increase of $2 million in the nine months ended September 30, 2024 due to increased levels of intercompany borrowings and an increase of $3 million and $7 million, respectively, due to higher long-term debt balances. Additionally, an increase on long-term debt and a higher interest rate on an increased level of short-term borrowings increased interest charges by $3 million and $3 million, respectively, in the nine months ended September 30, 2024.

Ameren Missouri

Interest charges decreased $1 million and increased $21 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods because of the following items:

• Issuances of long-term debt in March 2023, January 2024, and April 2024, which collectively increased interest charges by $11 million and $32 million, respectively.

• Interest charges reflected a deferral to a regulatory asset of interest associated with investments in eligible property, plant, and equipment not yet included in base rates, pursuant to PISA and RESRAM. Base rates were updated to include the eligible property, plant, and equipment in-service through December 31, 2022, when new customer rates became effective on July 9, 2023, pursuant to the June 2023 MoPSC electric rate order. This update to base rates resulted in a lower deferral of interest in 2024 pursuant to PISA and RESRAM that increased interest charges by $3 million in the nine months ended September 30, 2024.

• Higher level of short-term borrowings increased interest charges by $2 million in the three months ended September 30, 2024.

The above increases in the three and nine months ended September 30, 2024, compared with the year-ago periods, were partially offset by the following items:

• Increase in the borrowed funds capitalized as part of the allowance for funds used during construction of $4 million and $7 million, respectively, primarily due to higher average construction work in progress balances.

• Lower level of short-term borrowings decreased interest charges by $4 million in the nine months ended September 30, 2024.

• Interest charges reflected a deferral to a regulatory asset of interest associated with investments in eligible property, plant, and equipment not yet included in base rates, pursuant to PISA and RESRAM. Base rates were updated to include the eligible property, plant, and equipment in-service through December 31, 2022, when new customer rates became effective on July 9, 2023, pursuant to the June 2023 MoPSC electric rate order. This update to base rates resulted in a higher deferral of interest in 2024 pursuant to PISA and RESRAM that decreased interest charges by $6 million in the three months ended September 30, 2024.

Ameren Illinois

Interest charges increased $9 million and $27 million in the three and nine months ended September 30, 2024, respectively, compared with the year-ago periods, primarily because of the following:

Ameren Illinois Transmission

Interest charges increased by $6 million and $15 million, respectively, primarily because of issuances of long-term debt in May 2023 and June 2024 which increased interest charges by $3 million and $7 million, respectively. Additionally, an increase interest on long-term debt and a higher interest rate on an increased level of short-term borrowings increased interest charges by $3 million and $2 million, respectively, in the nine months ended September 30, 2024.

Ameren Illinois Electric Distribution

Interest charges increased by $2 million and $7 million, respectively, primarily because of issuances of long-term debt in May 2023 and June 2024.

Ameren Illinois Natural Gas

Interest charges increased by $1 million and $5 million, respectively, primarily because of issuances of long-term debt in May 2023 and June 2024.

Income Taxes

The following table presents effective income tax rates for the three and nine months ended September 30, 2024 and 2023:

						Three Months(a)												Nine Months**(a)**
						2024						2023						2024						2023
Ameren						11		%				12		%				13		%				13		%
Ameren Missouri						(2)		%				(3)		%				(1)		%				(3)		%
Ameren Illinois						24		%				25		%				24		%				25		%
Ameren Illinois Electric Distribution						20		%				21		%				19		%				24		%
Ameren Illinois Natural Gas						22		%				(b)						27		%				27		%
Ameren Illinois Transmission						27		%				27		%				27		%				26		%
Ameren Transmission						27		%				27		%				27		%				26		%

(a)Estimate of the annual effective income tax rate adjusted to reflect the tax effect of items discrete to the three and nine months ended September 30, 2024 and 2023.

(b)Not meaningful because of the insignificant amount of income/(loss) before income taxes.

See Note 12 – Income Taxes under Part I, Item 1, of this report for a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the Ameren Companies.

The effective tax rate was lower at Ameren Illinois Electric Distribution in the three and nine months ended September 30, 2024, compared with the year-ago periods, primarily because of an increase in excess deferred tax amortization pursuant to an ICC order, which was offset by a corresponding decrease in revenues.

LIQUIDITY AND CAPITAL RESOURCES

Collections from our tariff-based revenues are our principal source of cash provided by operating activities. A diversified retail customer mix, primarily consisting of rate-regulated residential, commercial, and industrial customers, provides us with a reasonably predictable source of cash. In addition to using cash provided by operating activities, we use available cash, drawings under committed credit agreements, commercial paper issuances, and/or, in the case of Ameren Missouri and Ameren Illinois, short-term affiliate borrowings to support normal operations and temporary capital requirements. We may reduce our short-term borrowings with cash provided by operations or, at our discretion, with long-term borrowings, or, in the case of Ameren Missouri and Ameren Illinois, with capital contributions from Ameren (parent). As of September 30, 2024, there have been no material changes other than in the ordinary course of business related to cash requirements arising from the long-term commitments for fuel for generation, purchased power, and natural gas for distribution as described under Liquidity and Capital Resources in Item 7 of the Form 10-K.

We expect to make significant capital expenditures over the next five years, supported by a combination of long-term debt and equity, as we invest in our electric and natural gas utility infrastructure to support overall system reliability, grid modernization, renewable energy target requirements, environmental compliance, and other improvements. For additional information about our long-term debt outstanding, including maturities due within one year, and the applicable interest rates, see Note 5 – Long-term Debt and Equity Financings under Part II, Item 8 of the Form 10-K and Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report. As part of its funding plan for capital expenditures, Ameren is using newly-issued shares of common stock to satisfy requirements under the DRPlus and employee benefit plans and expects to continue to do so through at least 2028. Additionally, Ameren has an ATM program under which Ameren may offer and sell from time to time common stock, which includes the ability to enter into forward sales agreements, subject to market conditions and other factors. There were no shares issued under the ATM program during the nine months ended September 30, 2024. As of September 30, 2024, Ameren had multiple forward sale agreements that could be settled under the ATM program with various counterparties relating to 4.7 million shares of common stock. Ameren expects to settle approximately $230 million of the forward sale agreements with physical delivery of 2.9 million shares of common stock by December 31, 2024. Including issuances under the DRPlus and employee benefit plans, Ameren plans to issue approximately $300 million of equity in 2024 and approximately $600 million of equity each year from 2025 to 2028. As of September 30, 2024, Ameren had approximately $615 million of common stock available for sale under the ATM program, which takes into account the forward sale agreements in effect as of September 30, 2024. The Ameren Companies expect their equity to total capitalization to support solid investment-grade credit ratings. See Long-term Debt and Equity below and Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information on the ATM program, including the forward sale agreements under the ATM program relating to common stock.

The following table presents net cash provided by (used in) operating, investing, and financing activities for the nine months ended September 30, 2024 and 2023:

			Net Cash Provided By Operating Activities																		Net Cash Used In Investing Activities																		Net Cash Provided By Financing Activities
			2024						2023						Variance						2024						2023						Variance						2024						2023						Variance
Ameren			$	1,946		(a)			$	2,031		(a)			$	(85)					$	(3,106)					$	(2,656)					$	(450)					$	1,212					$	655					$	557
Ameren Missouri			997						1,031						(34)						(1,932)						(1,338)						(594)						935						307						628
Ameren Illinois			1,067			(a)			1,026			(a)			41						(1,090)						(1,229)						139						82						237						(155)

(a)Both Ameren and Ameren Illinois’ cash provided by operating activities included cash outflows of $82 million and $84 million for the FEJA electric energy-efficiency rider and $20 million and $6 million for the customer generation rebate program for the nine months ended September 30, 2024 and 2023, respectively.

Cash Flows from Operating Activities

Our cash provided by operating activities is affected by fluctuations of trade accounts receivable, inventories, and accounts and wages payable, among other things, as well as the unique regulatory environment for each of our businesses. Substantially all expenditures related to fuel, purchased power, and natural gas purchased for resale are recovered from customers through rate adjustment mechanisms, which may be adjusted without a traditional regulatory rate review, subject to prudence reviews. Similar regulatory mechanisms exist for certain other operating expenses that can also affect the timing of cash provided by operating activities. The timing of cash payments for costs recoverable under our regulatory mechanisms differs from the recovery period of those costs. Additionally, the seasonality of our electric and natural gas businesses, primarily caused by seasonal customer rates and changes in customer demand due to weather, significantly affects the amount and timing of our cash provided by operating activities.

Ameren

Ameren’s cash provided by operating activities decreased $85 million in the first nine months of 2024, compared with the year-ago period. The following items contributed to the decrease:

• A $143 million increase in net collateral posted with counterparties, primarily due to changes in the market prices of power, natural gas, and other fuels.

• A $46 million decrease due to the timing of payments for accounts payable.

• A $45 million increase in interest payments, primarily due to an increase in the average outstanding debt and an increase in interest rates.

• A $29 million increase in the cost of natural gas held in storage, primarily at Ameren Illinois, because of higher volumes, partially offset by lower commodity prices.

• A $10 million increase in payroll taxes, primarily at Ameren Missouri, due to the absence of employee retention tax credits received in the year-ago period under the Coronavirus Aid, Relief, and Economic Security Act.

• A $10 million increase in medical benefit costs.

• A $6 million increase in pension and postretirement benefit plan contributions.

The following items partially offset the decrease in Ameren’s cash from operating activities between periods:

• A $90 million increase resulting from increased customer collections primarily from base rate increases effective July 1, 2023, at Ameren Missouri pursuant to the June 2023 electric rate order and base rate increases effective November 28, 2023, at Ameren Illinois pursuant to the November 2023 natural gas rate order and electric transmission rate base growth, partially offset by lower customer collections under cost recovery mechanisms at Ameren Missouri.

• A $37 million increase due to the transfer of production tax credits generated by the High Prairie Renewable and Atchison Renewable energy centers to unrelated third parties and lower income tax payments primarily due to lower taxable income compared to the year-ago period.

• A $34 million increase due to higher purchases of materials and supplies inventories in the year-ago period to support operations as levels were increased to mitigate against potential supply disruptions.

• A $22 million increase due to insurance proceeds received in 2024 related to workers’ compensation payments made in the year-ago period at Ameren Illinois.

• A $19 million increase due to workers’ compensation payments made in the year-ago period at Ameren Illinois.

• An $18 million increase due to higher coal purchases in the year-ago period to bring coal inventories back to targeted levels after transportation delays experienced in 2022.

Ameren Missouri

Ameren Missouri’s cash provided by operating activities decreased $34 million in the first nine months of 2024, compared with the year-ago period. The following items contributed to the decrease:

• A $92 million increase in net collateral posted with counterparties, primarily due to changes in the market prices of power, natural gas, and other fuels.

• A $42 million decrease due to the timing of payments for accounts payable and prepaid expenses.

• A $15 million increase in interest payments, primarily due to an increase in the average outstanding debt and an increase in interest rates.

• A $7 million increase in payroll taxes due to the absence of employee retention tax credits received in the year-ago period under the Coronavirus Aid, Relief, and Economic Security Act.

The following items partially offset the decrease in Ameren Missouri’s cash from operating activities between periods:

• A $61 million increase due to the transfer of production tax credits generated by the High Prairie Renewable and Atchison Renewable energy centers to unrelated parties, as well as an income tax refund from Ameren (parent), pursuant to the tax allocation agreement, primarily due to lower taxable income compared to the year-ago period.

• A $32 million increase due to higher purchases of materials and supplies inventories in the year-ago period to support operations as levels were increased to mitigate against potential supply disruptions.

• A $21 million increase resulting from increased customer collections primarily from base rate increases effective July 1, 2023, pursuant to the June 2023 electric rate order, partially offset by lower customer collections under cost recovery mechanisms.

• An $18 million increase due to higher coal purchases in the year-ago period to bring coal inventories back to targeted levels after transportation delays experienced in 2022.

Ameren Illinois

Ameren Illinois’ cash provided by operating activities increased $41 million in the first nine months of 2024, compared with the year-ago period. The following items contributed to the increase:

• A $57 million increase resulting from increased customer collections primarily from base rate increases effective November 28, 2023, pursuant to the November 2023 natural gas rate order and electric transmission rate base growth, and by increased customer collections under cost recovery mechanisms.

• A $52 million increase due to lower income tax payments to Ameren (parent), pursuant to the tax allocation agreement, primarily due to lower taxable income compared to the year-ago period.

• A $22 million increase due to insurance proceeds received in 2024 related to workers’ compensation payments made in the year-ago period.

• A $19 million increase due to workers’ compensation payments made in the year-ago period.

The following items partially offset the increase in Ameren Illinois’ cash from operating activities between periods:

• A $42 million increase in net collateral posted with counterparties, primarily due to changes in the market prices of power and natural gas.

• A $25 million increase in the cost of natural gas held in storage because of higher volumes, partially offset by lower commodity prices.

• A $21 million decrease due to the timing of payments for accounts payable.

• An $18 million increase in interest payments, primarily due to an increase in the average outstanding debt and an increase in interest rates.

Cash Flows from Investing Activities

Ameren’s cash used in investing activities increased $450 million during the first nine months of 2024, compared with the year-ago period, primarily as a result of a $458 million increase in capital expenditures, largely resulting from the acquisition of the Cass County and Boomtown solar projects at Ameren Missouri, partially offset by decreased expenditures for electric transmission infrastructure upgrades at Ameren Illinois. Ameren’s increase in capital expenditures was also partially offset by decreased expenditures for electric distribution infrastructure upgrades and natural gas infrastructure at Ameren Illinois due to steps taken by Ameren Illinois to align its 2024 operations with the ICC’s MYRP orders and November 2023 natural gas rate order.

Ameren Missouri’s cash used in investing activities increased $594 million during the first nine months of 2024, compared with the year-ago period, primarily as a result of a $584 million increase in capital expenditures, largely resulting from the acquisition of the Cass County and Boomtown solar projects.

Ameren Illinois’ cash used in investing activities decreased $139 million during the first nine months of 2024, compared with the year-ago period, primarily as a result of a $135 million decrease in capital expenditures, largely resulting from decreased expenditures for electric transmission infrastructure upgrades. Ameren Illinois’ capital expenditures also decreased as a result of reduced expenditures for electric distribution infrastructure upgrades and natural gas infrastructure due to steps taken by Ameren Illinois to align its 2024 operations with the ICC’s MYRP orders and November 2023 natural gas rate order.

Cash Flows from Financing Activities

Cash provided by, or used in, financing activities is a result of our financing needs, which depend on the level of cash provided by operating activities, the level of cash used in investing activities, the level of dividends, and our long-term debt maturities, among other things.

Ameren’s cash provided by consolidated financing activities increased $557 million during the first nine months of 2024, compared with the year-ago period. During the first nine months of 2024, Ameren utilized net proceeds from the issuance of long-term debt of $1.6 billion for capital expenditures, to repay then-outstanding short-term debt, and to repay $49 million of maturities of long-term debt at ATXI. During the first nine months of 2024, Ameren utilized proceeds from net commercial paper issuances of $1.0 billion along with cash on hand and cash provided by operating activities to repay $800 million of long-term debt maturities at Ameren (parent) and Ameren Missouri, and to fund, in part, capital expenditures. In comparison, during the first nine months of 2023, Ameren utilized net proceeds from the issuance of long-term debt of $1.0 billion for capital expenditures, to repay then-outstanding short-term debt, and to repay $100 million of long-term debt maturities. In addition, during the first nine months of 2023, Ameren utilized proceeds from net commercial paper issuances of $272 million along with cash provided by operating activities to fund, in part, capital expenditures. During the first nine months of 2024, Ameren paid common stock dividends of $535 million, compared with $496 million in the year-ago period, as a result of an increase in both the dividend rate and the number of common shares outstanding.

Ameren Missouri’s cash provided by financing activities increased $628 million during the first nine months of 2024, compared with the year-ago period. During the first nine months of 2024, Ameren Missouri utilized net proceeds from the issuance of long-term debt of $846 million for capital expenditures and to repay then-outstanding short-term debt. During the first nine months of 2024, Ameren Missouri utilized net commercial paper issuances totaling $406 million, capital contributions from Ameren (parent) of $350 million, and cash provided by operating activities to fund, in part, capital expenditures. Ameren Missouri also repaid $350 million of long-term debt maturities and $289 million of money pool borrowings during the first nine months of 2024. In comparison, during the first nine months of 2023, Ameren Missouri utilized net proceeds from the issuance of long-term debt of $499 million for capital expenditures and to repay then-outstanding short-term debt. During the first nine months of 2023, Ameren Missouri repaid net commercial paper borrowings totaling $172 million.

Ameren Illinois’ cash provided by financing activities decreased $155 million during the first nine months of 2024, compared with the year-ago period. During the first nine months of 2024, Ameren Illinois utilized proceeds from the issuance of long-term debt of $624 million to repay then-outstanding short-term debt. In addition, during the first nine months of 2024, Ameren Illinois repaid net commercial paper borrowings of $349 million and money pool borrowings of $135 million. In comparison, during the first nine months of 2023, Ameren Illinois utilized net proceeds from the issuance of long-term debt of $498 million to repay then-outstanding short-term debt and $100 million of long-term debt maturities. In addition, during the first nine months of 2023, Ameren Illinois repaid net commercial paper borrowings totaling $205 million and also received a $50 million capital contribution from Ameren (parent). During the first nine months of 2024, Ameren Illinois also paid common stock dividends of $50 million.

See Long-term Debt and Equity in this section for additional information on maturities and issuances of long-term debt, issuances of common stock, and noncash settlement of a financing obligation.

Credit Facility Borrowings and Liquidity

The following table presents Ameren’s consolidated liquidity as of September 30, 2024:

															Available at September 30, 2024
Ameren (parent) and Ameren Missouri:
Missouri Credit Agreement – borrowing capacity															$	1,400
Less: Ameren (parent) commercial paper outstanding															557
Less: Ameren Missouri commercial paper outstanding															576
Less: Letters of credit															17
Missouri Credit Agreement – subtotal															250
Ameren (parent) and Ameren Illinois:
Illinois Credit Agreement – borrowing capacity															1,200
Less: Ameren (parent) commercial paper outstanding															389
Less: Ameren Illinois commercial paper outstanding															17
Less: Ameren Illinois letters of credit															1
Illinois Credit Agreement – subtotal															793
Subtotal															$	1,043
Add: Cash and cash equivalents															17
Net Available Liquidity**(a)**															$	1,060

(a)Does not include Ameren’s forward equity sale agreements. See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information.

The Credit Agreements, among other things, provide $2.6 billion of credit until maturity in December 2027. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report for additional information on the Credit Agreements. During the nine months ended September 30, 2024, Ameren (parent), Ameren Missouri, and Ameren Illinois each issued commercial paper. Borrowings under the Credit Agreements and commercial paper issuances are based upon available interest rates at the time of the borrowing or issuance.

Ameren has a money pool agreement with and among its utility subsidiaries to coordinate and to provide for certain short-term cash and working capital requirements. As short-term capital needs arise, and based on availability of funding sources, Ameren Missouri and Ameren Illinois will access funds from the utility money pool, the Credit Agreements, or the commercial paper programs depending on which option has the lowest interest rates.

See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report for additional information on credit agreements, commercial paper issuances, Ameren’s money pool agreements and related borrowings, and relevant interest rates.

The issuance of short-term debt securities by Ameren’s utility subsidiaries is subject to FERC approval under the Federal Power Act. In January 2023, the FERC issued orders authorizing Ameren Missouri, Ameren Illinois, and ATXI to issue up to $1 billion, $1 billion, and $300 million, respectively, of short-term debt securities through January 2025.

The Ameren Companies continually evaluate the adequacy and appropriateness of their liquidity arrangements for changing business conditions. When business conditions warrant, changes may be made to existing credit agreements or to other borrowing arrangements, or other arrangements may be made.

Long-term Debt and Equity

The following table presents issuances (net of any issuance premiums or discounts) of long-term debt and equity, as well as maturities of long-term debt for the nine months ended September 30, 2024 and 2023:

			Month Issued, Redeemed, or Matured						2024						2023
Issuances of Long-term Debt
Ameren Missouri:
5.25% First mortgage bonds due 2054			January						$	347					$	—
5.45% First mortgage bonds due 2053			March						—						499
5.20% First mortgage bonds due 2034			April						499						—
Ameren Illinois:
4.95% First mortgage bonds due 2033			May						—						498
5.55% First mortgage bonds due 2054			June						624						—
ATXI:
5.17% Senior unsecured notes due 2039			August						70						—
5.42% Senior unsecured notes due 2053			August						70						—
Total Ameren long-term debt issuances									$	1,610					$	997
Issuances of Common Stock
Ameren:
DRPlus and 401(k)(a)(b)			Various						$	30					$	28
Total Ameren common stock issuances(c)									$	30					$	28
Maturities of Long-term Debt
Ameren:
2.50% Senior unsecured notes due 2024			September						$	450					$	—
Ameren Missouri:
Audrain County agreement (Audrain County CT) due 2023			January						—						240			(d)
3.50% Senior secured notes due 2024			April						350						—
Ameren Illinois:
0.375% First mortgage bonds due 2023			June						—						100
ATXI:
3.43% Senior unsecured notes due 2050			August						49						—
Total Ameren long-term debt maturities									$	849					$	340

(a)Ameren issued a total of 0.4 million and 0.4 million shares of common stock under its DRPlus and 401(k) plan for the nine months ended September 30, 2024 and 2023, respectively.

(b)Excludes a $7 million and $7 million receivable at September 30, 2024 and 2023, respectively.

(c)Excludes 0.2 million and 0.5 million shares of common stock valued at $16 million and $37 million issued for no cash consideration in connection with stock-based compensation for the nine months ended September 30, 2024 and 2023, respectively.

(d)In January 2023, Ameren Missouri and Audrain County mutually agreed to terminate a financing obligation agreement related to the CT energy center in Audrain County, which was scheduled to expire in December 2023. No cash was exchanged in connection with the termination of the agreement as the $240 million principal amount of the financing obligation due from Ameren Missouri was equal to the amount of bond service payments due to Ameren Missouri.

In October 2024, Ameren Missouri issued $450 million of 5.125% first mortgage bonds due March 2055, with interest payable semiannually on March 15 and September 15 of each year, beginning March 15, 2025. Net proceeds from this issuance were used for capital expenditures and to repay short-term debt.

See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information, including proceeds from issuances of long-term debt, the use of those proceeds, Ameren’s forward equity sale agreements, the ATM program, and capital contributions received by Ameren Missouri from Ameren (parent).

Indebtedness Provisions and Other Covenants

At September 30, 2024, the Ameren Companies were in compliance with the provisions and covenants contained in their credit agreements, indentures, and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreements. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and Note 4 – Short-term Debt and Liquidity and Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for a discussion of provisions, applicable cross-default provisions, and covenants contained in our credit agreements, in ATXI’s note purchase agreements, and in certain of the Ameren Companies’ indentures and articles of incorporation.

We consider access to short-term and long-term capital and credit markets to be a significant source of funding for capital requirements not satisfied by cash provided by our operating activities. Inability to raise capital on reasonable terms, particularly during times of uncertainty in the capital and credit markets, could negatively affect our ability to maintain and expand our businesses. After assessing their respective current operating performance, liquidity, and credit ratings (see Credit Ratings below), Ameren, Ameren Missouri, and Ameren Illinois each believes that it will continue to have access to the capital and credit markets on reasonable terms. However, events beyond Ameren’s, Ameren Missouri’s, or Ameren Illinois’ control may create uncertainty in the capital and credit markets or make access to the capital and credit markets uncertain or limited. Such events could increase our cost of capital and adversely affect our ability to access the capital and credit markets.

Dividends

The amount and timing of dividends payable on Ameren’s common stock are within the sole discretion of Ameren’s board of directors. Ameren’s board of directors has not set specific targets or payout parameters when declaring common stock dividends, but it considers various factors, including Ameren’s overall payout ratio, payout ratios of our peers, projected cash flow and potential future cash flow requirements, historical earnings and cash flow, projected earnings, impacts of regulatory orders or legislation, and other key business considerations. Ameren expects its dividend payout ratio to be between 55% and 65% of annual earnings over the next few years.

See Note 4 – Short-term Debt and Liquidity and Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for additional discussion of covenants and provisions contained in certain of the Ameren Companies’ financial agreements and articles of incorporation that would restrict the Ameren Companies’ payment of dividends in certain circumstances. At September 30, 2024, none of these circumstances existed at Ameren, Ameren Missouri, or Ameren Illinois and, as a result, these companies were not restricted from paying dividends.

The following table presents common stock dividends declared and paid by Ameren Corporation to its common shareholders and by Ameren subsidiaries to their parent, Ameren Corporation, for the nine months ended September 30, 2024 and 2023:

			Nine Months
			2024						2023
Ameren			$	535					$	496
Ameren Illinois			50						—
ATXI			—						95

Credit Ratings

Our credit ratings affect our liquidity, our access to the capital and credit markets, our cost of borrowing under our credit facilities and our commercial paper programs, and our collateral posting requirements under commodity contracts.

The following table presents the principal credit ratings by Moody’s and S&P, as applicable, effective on the date of this report:

						Moody’s						S&P
Ameren:
Issuer/corporate credit rating						Baa1						BBB+
Senior unsecured debt						Baa1						BBB
Commercial paper						P-2						A-2
Ameren Missouri:
Issuer/corporate credit rating						Baa1						BBB+
Secured debt						A2						A
Senior unsecured debt						Baa1						Not Rated
Commercial paper						P-2						A-2
Ameren Illinois:
Issuer/corporate credit rating						A3						BBB+
Secured debt						A1						A
Senior unsecured debt						A3						BBB+
Commercial paper						P-2						A-2
ATXI:
Issuer credit rating						A2						Not Rated
Senior unsecured debt						A2						Not Rated

A credit rating is not a recommendation to buy, sell, or hold securities. It should be evaluated independently of any other rating. Ratings are subject to revision or withdrawal at any time by the rating organization.

Collateral Postings

Any weakening of our credit ratings may reduce access to capital and trigger additional collateral postings and prepayments. Such changes may also increase the cost of borrowing, resulting in an adverse effect on earnings. Cash collateral postings and prepayments made with external parties, including postings related to exchange-traded contracts were immaterial and cash collateral posted by external parties were $61 million for Ameren and Ameren Illinois at September 30, 2024. A sub-investment-grade issuer or senior unsecured debt rating (below “Baa3” from Moody’s or below “BBB-” from S&P) at September 30, 2024, could have resulted in Ameren, Ameren Missouri, or Ameren Illinois being required to post additional collateral or other assurances for certain trade and contractual obligations amounting to $944 million, $870 million, and $74 million, respectively.

Changes in commodity prices could trigger additional collateral postings and prepayments. Based on credit ratings at September 30, 2024, if market prices were 15% higher or lower than September 30, 2024 levels in the next 12 months and 20% higher or lower thereafter through the end of the term of the commodity contracts, then Ameren, Ameren Missouri, and Ameren Illinois could be required to post an immaterial amount, compared to each company’s liquidity, of collateral or provide other assurances for certain trade and contractual obligations.

OUTLOOK

Below are some key trends, events, and uncertainties that may reasonably affect our results of operations, financial condition, or liquidity, as well as our ability to achieve strategic and financial objectives, for 2024 and beyond. For additional information regarding recent rate orders, lawsuits, and pending requests filed with state and federal regulatory commissions, including those discussed below, see Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report and Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K.

Operations

*•*The PISA permits Ameren Missouri to defer and recover 85% of the depreciation expense for investments in qualifying property, plant, and equipment placed in service and not included in base rates. Investments not eligible for recovery under the PISA include amounts related to new nuclear and natural gas generating units and service to new customer premises. Additionally, the PISA permits Ameren Missouri to earn a return at the applicable WACC on rate base that incorporates those qualifying investments, as well as changes in total accumulated depreciation excluding retirements and plant-related deferred income taxes since the previous regulatory rate review. The

regulatory asset for accumulated PISA deferrals also earns a return at the applicable WACC until added to rate base prospectively. Ameren Missouri recognizes an offset to “Interest Charges” on its consolidated statement of income for its carrying cost of debt relating to each return allowed under the PISA, with the difference between the applicable WACC and its carrying cost of debt recognized in revenues when recovery of PISA deferrals is reflected in customer rates. Approved PISA deferrals are recovered over a period of 20 years following a regulatory rate review. Additionally, under the RESRAM, Ameren Missouri is permitted to recover the 15% of depreciation expense not recovered under the PISA, and earn a return at the applicable WACC for investments in renewable generation plant placed in service to comply with Missouri’s renewable energy standard. Accumulated RESRAM deferrals earn carrying costs at short-term interest rates. The PISA and the RESRAM mitigate the effects of regulatory lag between regulatory rate reviews. Those investments not eligible for recovery under the PISA and the remaining 15% of certain property, plant, and equipment placed in service, unless eligible for recovery under the RESRAM, remain subject to regulatory lag. As a result of the PISA election, additional provisions of the law apply to Ameren Missouri, including limitations on electric customer rate increases. Pursuant to a Missouri law that became effective in August 2022, Ameren Missouri’s PISA election was extended through December 2028 and an additional extension through December 2033 is allowed if requested by Ameren Missouri and approved by the MoPSC, among other things. This law also established a 2.5% annual limit on increases to the electric service revenue requirement used to set customer rates, compared to the revenue requirement established in the immediately preceding rate order, due to the inclusion of incremental PISA deferrals in the revenue requirement. The limitation will be effective for revenue requirements approved by the MoPSC after January 1, 2024.

*•*In June 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for electric service by $446 million. The MoPSC proceeding relating to the proposed electric service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by May 2025 and new rates effective by June 2025. Ameren Missouri cannot predict the level of any electric service rate change the MoPSC may approve, whether the requested regulatory recovery mechanisms will be continued, or whether any rate change that may eventually be approved will be sufficient for Ameren Missouri to recover its costs and earn a reasonable return on its investments when the rate change goes into effect.

• In September 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for natural gas delivery service by $40 million. The MoPSC proceeding relating to the proposed natural gas delivery service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by August 2025 and new rates effective by September 2025. Ameren Missouri cannot predict the level of any natural gas delivery service rate change the MoPSC may approve, whether the requested regulatory recovery mechanisms will be continued, or whether any rate change that may eventually be approved will be sufficient for Ameren Missouri to recover its costs and earn a reasonable return on its investments when the rate change goes into effect.

• In 2018, the MoPSC issued an order approving Ameren Missouri’s MEEIA 2019 plan. The plan includes a portfolio of customer energy-efficiency and demand response programs through December 2024. Ameren Missouri intends to invest $76 million in 2024. The plan includes the use of the MEEIA rider, which allows Ameren Missouri to collect from customers its actual MEEIA program costs and related lost electric revenues. In addition, the plan includes a performance incentive that provides Ameren Missouri an opportunity to earn revenues by achieving certain customer energy-efficiency goals. If the target program spending goal is achieved for 2024, the performance incentive would result in revenues of $12 million in 2024.

• In January 2024, Ameren Missouri filed a proposed customer energy-efficiency plan with the MoPSC under the MEEIA. In October 2024, Ameren Missouri, the MoOPC, and other intervenors filed a nonunanimous stipulation and agreement with the MoPSC for a three-year plan, which includes a portfolio of customer energy-efficiency and demand response programs, along with the continued use of the MEEIA rider discussed above. If the agreement is approved, Ameren Missouri intends to invest $51 million annually in 2025 and 2026 and $22 million in 2027 in the proposed customer energy-efficiency and demand response programs. In addition, the agreement requested performance incentives applicable to each plan year to earn revenues by achieving certain spending and demand response goals. If 100% of the goals are achieved in 2025, 2026, and 2027, Ameren Missouri would earn performance incentive revenues of $5 million, $5 million, and $2 million, respectively. Ameren Missouri expects a decision by the MoPSC in the fourth quarter of 2024, but cannot predict the ultimate outcome of this regulatory proceeding.

• Ameren Illinois and ATXI use a forward-looking rate calculation with an annual revenue requirement reconciliation for each company’s electric transmission business. Based on expected rate base and the currently allowed 10.48% ROE, which includes a 50-basis-point incentive adder for participation in an RTO, the revenue requirements that will be included in 2025 rates for Ameren Illinois’ and ATXI’s electric transmission businesses are $643 million and $232 million, respectively. These revenue requirements represent increases in Ameren Illinois’ and ATXI’s revenue requirements of $94 million and $9 million, respectively, from the revenue requirements reflected in 2024 rates, primarily due to higher expected rate base. These rates will affect Ameren Illinois’ and ATXI’s cash receipts during 2025, but will not determine their respective electric transmission service operating revenues, which will instead be based on 2025 actual recoverable costs, rate base, and a return on rate base at the applicable WACC as calculated under the FERC formula ratemaking framework.

• The allowed base ROE for FERC-regulated transmission rates previously charged under the MISO tariff has been the subject of pending proceedings since 2013. In October 2024, the FERC issued an order, which decreased the allowed base ROE from 10.02% to 9.98% and required refunds, with interest, for the periods from November 2013 to February 2015 and from late September 2016 forward. In March 2020, the FERC issued a Notice of Proposed Rulemaking on its transmission incentives policy, which proposed to increase the incentive ROE for participation in an RTO to 100 basis points from the current 50 basis points and revised the parameters for awarding incentives, while limiting the overall incentives to a cap of 250 basis points, among other things. In April 2021, the FERC issued a Supplemental Notice of Proposed Rulemaking, which proposed to modify the Notice of Proposed Rulemaking’s incentive for participation in an RTO by limiting this incentive for utilities that join an RTO to 50 basis points and only allowing them to earn the incentive for three years, among other things. If this proposal is included in a final rule, Ameren Illinois and ATXI would no longer be eligible for the 50 basis point RTO incentive adder, prospectively. The FERC is under no deadline to issue a final rule on this matter. Ameren is unable to predict the ultimate impact of any changes to the FERC’s incentives policy. A 50-basis-point change in the FERC-allowed ROE would affect Ameren’s and Ameren Illinois’ annual net income by an estimated $16 million and $11 million, respectively, based on each company’s 2024 projected rate base.

• Pursuant to December 2022 and March 2021 ICC orders, Ameren Illinois used the IEIMA formula framework to establish annual electric distribution service rates effective through 2023, and reconciled the related revenue requirement for customer rates established for 2023. As such, Ameren Illinois’ 2023 revenues reflected actual recoverable costs, year-end rate base, and a return at the applicable WACC, with the ROE component based on the annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points. By law, the decoupling provisions extend beyond 2023, which ensures that Ameren Illinois’ electric distribution revenues authorized in a regulatory rate review are not affected by changes in sales volumes. In April 2024, Ameren Illinois filed for a reconciliation adjustment to its 2023 electric distribution service revenue requirement with the ICC. In July 2024, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $158 million. An ICC decision in this proceeding is required by December 2024, and any approved adjustment would be collected from customers in 2025. This is the final revenue requirement reconciliation under the IEIMA formula framework.

• Pursuant to the CEJA, which was enacted in September 2021, Ameren Illinois may file an MYRP with the ICC to establish base rates for electric distribution service to be charged to customers for each calendar year of a four-year period. The base rates for a particular calendar year are based on forecasted recoverable costs and an ICC-determined ROE applied to Ameren Illinois’ forecasted average annual rate base using a forecasted capital structure, with a common equity ratio of up to 50% being deemed prudent and reasonable by law and a higher equity ratio requiring specific ICC approval. The ROE determined by the ICC for each calendar year of the four-year period is subject to annual adjustments based on certain performance incentives and penalties. An MYRP allows Ameren Illinois to reconcile electric distribution service rates to its actual revenue requirement on an annual basis, subject to a reconciliation cap and adjustments to the ROE. Under the MYRP discussed below, Ameren Illinois’ 2024 electric distribution service revenues will be based on its 2024 actual recoverable costs, 2024 year-end rate base, and an ROE of 8.72%, as adjusted for any performance incentives or penalties, provided the actual revenue requirement does not exceed the reconciliation cap. If a given year’s revenue amount collected from customers varies from the approved revenue requirement, an adjustment is made to electric operating revenues with an offset to a regulatory asset or liability to reflect that year’s actual revenue requirement, independent of actual sales volumes. The regulatory balance is then collected from, or refunded to, customers within two years from the end of the applicable annual period. Ameren Illinois’ existing riders remain effective under the MYRP discussed below, and will continue to remain effective beyond 2027 whether it elects to file an MYRP or a traditional regulatory rate review. Additionally, electric distribution service revenues continue to be decoupled from sales volumes under either election.

• In December 2023, the ICC issued an order in Ameren Illinois' MYRP proceeding approving base rates for electric distribution services for 2024 through 2027 and rejecting Ameren Illinois' Grid Plan, which was addressed as part of the MYRP proceeding. Rate changes consistent with the December 2023 order became effective in January 2024 and remained effective through late June 2024, when new rates became effective pursuant to the June 2024 ICC rehearing order discussed below. The December 2023 order adopted an alternative methodology to establish a rate base and revenue requirements for the years 2024 through 2027 using Ameren Illinois’ previously approved 2022 year-end rate base. In January 2024, the ICC partially denied a rehearing requested by Ameren Illinois to revise the allowed ROE in the December 2023 order and granted Ameren Illinois’ rehearing request to reconsider the rate base for each year of the MYRP and to include a base level of investments to maintain grid reliability in each year of the MYRP. In June 2024, the ICC issued an order on Ameren Illinois’ rehearing request, approving revenue requirements for electric distribution services for 2024, 2025, 2026, and 2027 of $1,196 million, $1,282 million, $1,350 million, and $1,397 million, respectively. New rates became effective in late June 2024. Using the 2023 revenue requirement as a starting point, the approved revenue requirements in the ICC’s June 2024 rehearing order represent a cumulative four-year increase of $285 million. In July 2024, Ameren Illinois filed a request for rehearing of the ICC’s June 2024 rehearing order to include an asset associated with other postretirement benefits in the rate base. Subsequently, in August 2024, the ICC denied the rehearing request. In January 2024, Ameren Illinois filed an appeal of the December 2023 ICC order and subsequently updated the appeal filing in September 2024 to include the June 2024 rehearing order regarding the inclusion of an asset associated with other postretirement benefits in the rate base to the Illinois Appellate Court for the Fifth Judicial District. The court is under no deadline to address the appeal. In September 2024, Ameren Illinois filed an update to its revised Grid Plan and a request to update the associated MYRP revenue requirements for 2024, 2025, 2026, and 2027 to $1,215 million, $1,299 million, $1,385 million, and $1,444 million, respectively. An ICC decision on the revised Grid Plan and updated revenue requirements is expected in December 2024 with rates effective in January 2025. Using the 2023 revenue requirement as a starting point, the requested revenue requirements in Ameren Illinois’ September 2024 revised MYRP filing represent a cumulative four-year increase of $332 million. Ameren Illinois cannot predict the ultimate outcome of the appeal to the Illinois Appellate Court for the Fifth Judicial District, its revised Grid Plan filing, or its request to update the associated MYRP revenue requirements for 2024 through 2027. Ameren Illinois has taken prudent steps to align its 2024 operations with the ICC orders, while continuing to ensure safe and adequate service is maintained. This includes reductions to Ameren Illinois’ capital expenditure and operations and maintenance expense plans.

*•*Pursuant to Illinois law, Ameren Illinois’ electric energy-efficiency investments are deferred as a regulatory asset and earn a return at the applicable WACC, with the ROE component based on the annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points. The allowed ROE on electric energy-efficiency investments can be increased or decreased by up to 200 basis points, depending on the achievement of annual energy savings goals. While the ICC has approved a plan for Ameren Illinois to invest approximately $120 million per year in electric energy-efficiency programs through 2025, the ICC has the ability to reduce the amount of electric energy-efficiency savings goals in future program years if there are insufficient cost-effective programs available, which could reduce the investments in electric energy-efficiency programs.

• In November 2023, the ICC issued an order in Ameren Illinois’ January 2023 natural gas delivery service regulatory rate review, which resulted in an increase to its annual revenues for natural gas delivery service of $112 million. The new rates became effective on November 28, 2023. In December 2023, Ameren Illinois filed a request for rehearing with the ICC to revise the approved ROE and capital structure common equity percentage, and reverse an approximately $93 million reduction of planned distribution and transmission capital investments included in the order, among other things. In January 2024, the ICC denied Ameren Illinois’ rehearing request. Subsequently, in January 2024, Ameren Illinois filed an appeal of the November 2023 ICC order to the Illinois Appellate Court for the Fifth Judicial District. The court is under no deadline to address the appeal. Ameren Illinois cannot predict the ultimate outcome of this appeal. Ameren Illinois has taken prudent steps to align its 2024 operations with the ICC order, while continuing to ensure safe and adequate service is maintained. This includes reductions to Ameren Illinois’ capital expenditure and operations and maintenance expense plans.

• Ameren Illinois expects to file for a natural gas delivery service regulatory rate review in early 2025, with a future test year ended December 31, 2026.

• Ameren Missouri’s next refueling and maintenance outage at its Callaway energy center is scheduled for the spring of 2025. During a scheduled refueling, which occurs every 18 months, maintenance expenses are deferred as a regulatory asset and amortized until the completion of the next refueling and maintenance outage. During an outage, depending on the availability of its other generation sources and the market prices for power, Ameren Missouri’s purchased power costs may increase and the amount of excess power available for sale may decrease versus non-outage years. Changes in purchased power costs and excess power available for sale are included in the FAC, which results in limited impacts to earnings. In addition, Ameren Missouri may incur increased non-nuclear energy center maintenance costs in non-outage years.

• In September 2023, the United States District Court for the Eastern District of Missouri granted Ameren Missouri’s request to modify a September 2019 remedy order issued by the district court in order to allow the retirement of the Rush Island Energy Center in advance of its previously expected retirement date of 2039, in lieu of installing a flue gas desulfurization system. Ameren Missouri retired the

Rush Island Energy Center on October 15, 2024. The United States Department of Justice is seeking an order from the district court providing for additional mitigation relief related to prior emissions. In November 2024, Ameren Missouri and the United States Department of Justice reached an agreement in principle, which, if approved by the district court, would resolve all outstanding claims in this case and would require Ameren Missouri to fund a program to provide electric buses and charging stations to schools in the metro St. Louis area and a program to provide air purifiers to eligible Ameren Missouri electric residential customers. These programs are estimated to cost approximately $64 million. As of September 30, 2024, Ameren and Ameren Missouri recorded liabilities of $64 million related to the cost of these programs. For additional information on the NSR and Clean Air Act litigation, see Note 9 – Commitments and Contingencies under Part I, Item 1, of this report.

• Pursuant to Illinois law, Ameren Missouri's natural gas-fired energy centers in Illinois are subject to annual limits on emissions, including CO2 and NOx. Further reductions to emissions limits will become effective between 2030 and 2040, resulting in the closure of the Venice Energy Center by the end of 2029. The reductions could also limit the operations of Ameren Missouri's four other natural gas-fired energy centers located in the state of Illinois, and will result in their closure by 2040. These energy centers are utilized to support peak loads. Subject to conditions in the CEJA, these energy centers may be allowed to exceed the emissions limits in order to maintain reliability of electric utility service.

• Although the pace of inflation has slowed recently, we are still observing elevated inflation levels that continue to put pressure on the prices of labor, services, materials, and supplies, as well as elevated interest rates. Ameren Missouri and Ameren Illinois are generally allowed to pass on to customers prudently incurred costs for fuel, purchased power, and natural gas supply. Additionally, for certain non-commodity cost changes, the use of trackers, riders, formula ratemaking, and future test years, as applicable, mitigates our exposure. The elevated inflation levels and elevated interest rates could impact our ability to control costs and/or make substantial investments in our businesses, including our ability to recover costs and investments, and to earn our allowed ROEs within frameworks established by our regulators, while maintaining rates that are affordable to our customers. In addition, the elevated inflation levels and elevated interest rates could adversely affect our customers’ usage of, or payment for, our services.

• Ameren Missouri and Ameren Illinois continue to make infrastructure investments and expect to seek increases to electric and natural gas rates to recover the cost of investments and earn an adequate return. Ameren Missouri and Ameren Illinois will also seek new, or to maintain existing, regulatory and legislative solutions to address regulatory lag and to support investment in their utility infrastructure for the benefit of their customers. Ameren Missouri and Ameren Illinois continue to face cost recovery pressures, elevated inflation levels, higher cost of debt, customer conservation efforts, the impacts of additional customer energy-efficiency programs, and increased customer use of increasingly cost-effective advancements in innovative energy technologies, including private generation and energy storage. We expect a net increase in demand resulting from the electrification of the economy, including in the transportation sector. In addition, a new 250-MW data center is expected to be constructed in Ameren Missouri’s service territory and is expected to be in service by 2026. Several other entities in various industries, including data center and manufacturing, are considering either locating or expanding their operations within our service territories. We expect that increased investments, including expected future investments for environmental compliance, system reliability improvements, and new generation sources, will result in rate base and revenue growth but also higher depreciation and financing costs.

Liquidity and Capital Resources

• In September 2023, Ameren Missouri filed its 2023 IRP with the MoPSC, which includes Ameren Missouri’s preferred plan for meeting customers’ projected long-term energy needs in a manner that maintains system reliability and customer affordability while transitioning to clean energy generation in an environmentally responsible manner. In connection with this plan, Ameren is continuing to target net-zero carbon emissions by 2045, as well as a 60% reduction by 2030 and an 85% reduction by 2040 based on 2005 levels. Ameren’s goals include both reduction of direct emissions from operations (scope 1), as well as electricity usage at Ameren buildings (scope 2), including other greenhouse gas emissions of methane, nitrous oxide, and sulfur hexafluoride. Achieving these goals will be dependent on a variety of factors, including cost-effective advancements in innovative clean energy technologies and constructive federal and state energy and economic policies. The preferred plan includes, among other things, the following:

• adding an 800-MW natural gas-fired simple-cycle energy center by 2027, which will be realized through the Castle Bluff Natural Gas Project discussed below, and an additional 1,200-MW natural gas-fired combined-cycle energy center by 2033;

• adding 2,800 MWs of renewable generation by 2030, which includes the solar generation facilities discussed below, and an additional 1,900 MWs by 2036;

• adding 400 MWs of battery storage by 2030 and an additional 400 MWs by 2035;

• adding 1,200 MWs of other clean dispatchable generation resources by 2040 and an additional 1,200 MWs by 2043;

• retiring all of Ameren Missouri’s coal-fired energy centers by 2042;

• accelerating the retirement date of the Rush Island coal-fired energy center, which was retired on October 15, 2024;

• extending the retirement date of the Sioux coal-fired energy center from 2030 to 2032 to ensure reliability during the transition to clean energy generation, which is subject to the approval of a change in depreciable lives of the energy center’s assets by the MoPSC;

• retiring 1,800 MWs of Ameren Missouri’s natural gas-fired energy centers by 2040 to comply with Illinois law;

• the continued implementation of customer energy-efficiency and demand response programs; and

• the expectation that Ameren Missouri will seek and receive NRC approval for an extension of the operating license for the Callaway Energy Center beyond its current 2044 expiration date.

Expected capital expenditures through 2028 related to the facilities discussed above are included in Ameren’s and Ameren Missouri’s expected capital investments discussed below. Ameren Missouri’s plan could be affected by, among other factors: Ameren Missouri’s ability to obtain CCNs from the MoPSC, and any other required approvals for the addition of renewable resources or natural gas-fired generation, retirement of energy centers, and new or continued customer energy-efficiency programs; the ability to enter into agreements for renewable or natural gas-fired generation and acquire or construct that generation at a reasonable cost; the ability of suppliers, contractors, and developers to meet contractual commitments and timely complete projects, which is dependent upon the availability of necessary labor, materials, and equipment, geopolitical conflict, or government actions, among other things; changes in the scope and timing of projects; the ability to qualify for, and use or transfer, federal production or investment tax credits; the cost of wind, solar, and other renewable generation and battery storage technologies; the cost of natural gas or hydrogen CT technologies; the ability to maintain system reliability during and after the transition to clean energy generation; new and/or changes in environmental regulations, including those related to CO2 and other greenhouse gas emissions; energy prices and demand; Ameren Missouri’s ability to obtain necessary rights-of-way, easements, and transmission interconnection agreements at an acceptable cost and in a timely fashion; the ability to earn an adequate return on invested capital; and the ability to raise capital on reasonable terms. A new data center is expected to be constructed in Ameren Missouri’s service territory by 2026 and several entities are considering either locating or expanding their operations within Ameren Missouri’s service territory. As such, Ameren Missouri currently expects to update its 2023 IRP by February 2025, following its evaluation of potential load growth and its generation portfolio. The next integrated resource plan is required to be filed by October 2026.

• In June 2024, the MoPSC issued a financing order authorizing the issuance of securitized utility tariff bonds by a wholly owned, special purpose subsidiary of Ameren Missouri to finance approximately $470 million of costs related to the planned accelerated retirement of the Rush Island Energy Center, which includes the expected remaining unrecovered net plant balance associated with the facility, among other costs. Ameren Missouri will collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance. The financing order also includes a determination that the decision to retire the Rush Island Energy Center was reasonable and prudent. The MoPSC did not make a determination regarding the prudency of Ameren Missouri's prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation discussed in Note 9 – Commitments and Contingencies under Part I, Item 1, of this report. However, claims regarding such actions could be considered in future regulatory proceedings. Base rate revenues relating to the recovery of the Rush Island Energy Center are being deferred as a regulatory liability since the October 15, 2024 retirement date of the facility.

• Ameren Missouri, and certain subsidiaries of Ameren Missouri, are parties to agreements to acquire and/or construct various generation facilities. All regulatory approvals have been obtained. Ameren Missouri acquired the Cass County, Boomtown, and Huck Finn solar projects in June 2024, September 2024, and October 2024, respectively. These three acquisitions collectively represent a purchase price of approximately $0.9 billion. In October 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement filed by Ameren Missouri, the MoPSC staff, and other intervenors requesting a CCN for the Castle Bluff Natural Gas Project. The order also includes the use of a post-construction cost deferral related to the project which allows Ameren Missouri to defer and recover depreciation expense, financing costs, and applicable income taxes incurred from the date the project is placed in service to the date when project costs are reflected in updated base rates as a result of a regulatory rate review. The period of deferral would be limited to the earlier of the time the project costs are reflected in base rates or six months. All of the generation facilities are aligned with the 2023 IRP discussed above, and expected capital expenditures related to these facilities are included in Ameren’s and Ameren Missouri’s expected capital investments discussed below.

• Through 2028, we expect to make significant capital expenditures to improve our electric and natural gas utility infrastructure, with a major portion directed to our transmission and distribution systems. We estimate that we will invest up to $22.8 billion (Ameren Missouri – up to $13.5 billion; Ameren Illinois – up to $7.6 billion; ATXI – up to $1.7 billion) of capital expenditures during the period from 2024 through 2028. Ameren’s and Ameren Missouri’s estimates include $3.3 billion of renewable generation investments and $2.7 billion of dispatchable generation investments through 2028, consistent with Ameren Missouri’s 2023 IRP. Ameren’s and Ameren Illinois’ estimates include investments necessary to meet compliance requirements of the CEJA, while continuing to ensure safe and adequate service is maintained. Ameren Illinois’ estimates may be revised as a result of future ICC orders related to its current MYRP.

• In 2021, the MISO issued a report outlining a preliminary long-range transmission planning roadmap of projects through 2039, which considers the rapidly changing generation mix within MISO resulting from significant additions of renewable generation, actual and

expected generation plant closures, and state mandates or goals for clean energy or carbon emissions reductions. In July 2022, the MISO approved the first tranche of projects under the roadmap. A portion of these projects were assigned to various utilities, of which Ameren was awarded projects that are estimated to cost approximately $1.8 billion, based on the MISO’s cost estimate. Related to these projects, Ameren began substation upgrades in May 2024 in advance of transmission line construction, which is expected to begin in 2026, with forecasted completion dates near the end of this decade. In addition, the MISO awarded two competitive bid projects to ATXI in the fourth quarter of 2023 and one in April 2024 that represent a total estimated investment of approximately $220 million for ATXI. In February 2024, Ameren Illinois and ATXI filed a request for a CCN, among other things, with the ICC related to the portion of the MISO long-range transmission projects they will construct within the ICC’s jurisdiction. A decision by the ICC is expected by mid-2025. In July 2024, ATXI filed a request for a CCN, among other things, with the MoPSC related to a portion of the MISO long-range transmission projects that it expects to construct within the MoPSC’s jurisdiction. A decision by the MoPSC is expected by mid-2025. In September 2024, the MISO revised a proposed first set of second tranche projects with estimated costs of $21.8 billion, which includes projects located in our service territories of $3.6 billion, based on the MISO’s cost estimate. The MISO is expected to approve this set of projects by the end of 2024. The MISO expects to begin developing an additional set of second tranche projects in 2025.

• Environmental regulations, including those related to CO2 emissions, or other actions taken by the EPA or state regulators, or requirements that may result from the NSR and Clean Air Act Litigation, could result in significant increases in capital expenditures and operating costs. Regulations can be reviewed and repealed, and replacement or alternative regulations can be proposed or adopted by the regulatory agencies, including the EPA. See Note 9 – Commitments and Contingencies under Part I, Item 1, of this report, for additional information on environmental matters, including the NSR and Clean Air Act litigation. The ultimate implementation of any of these new regulations, as well as the timing of any such implementation, is uncertain. However, the individual or combined effects of existing and new environmental regulations could result in significant capital expenditures, increased operating costs, or the closure or alteration of some of Ameren Missouri’s coal and natural gas-fired energy centers. Ameren Missouri’s operating costs and capital expenditures are subject to MoPSC prudence reviews, which could result in cost disallowances, as well as regulatory lag. The cost of Ameren Illinois’ purchased power and natural gas purchased for resale could increase. However, Ameren Illinois expects that these costs would be recovered from customers with no material adverse effect on its results of operations, financial position, or liquidity. Ameren’s and Ameren Missouri’s earnings could benefit from increased investment to comply with environmental regulations if those investments are reflected and recovered on a timely basis in customer rates.

• The Ameren Companies have multiyear credit agreements that cumulatively provide $2.6 billion of credit through December 2027, subject to a 364-day repayment term for Ameren Missouri and Ameren Illinois, with the option to seek incremental commitments to increase the cumulative credit provided to $3.2 billion. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and Note 4 – Short-term Debt and Liquidity under Part II, Item 8, of the Form 10-K for additional information regarding the Credit Agreements. See Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for long-term debt maturities from 2024 to 2028 and beyond at Ameren (parent), Ameren Missouri, Ameren Illinois, and ATXI. See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for outstanding forward sale agreements under the ATM and issuances and maturities of long-term debt in 2024 through the date of this report. The use of cash provided by operating activities and short-term borrowings to fund capital expenditures and other long-term investments at the Ameren Companies frequently results in a working capital deficit, defined as current liabilities exceeding current assets, as was the case at September 30, 2024, for Ameren, Ameren Missouri, and Ameren Illinois. Ameren, Ameren Missouri, and Ameren Illinois each believe that their liquidity is adequate given their respective expected operating cash flows, capital expenditures, and financing plans, and expect to continue to have access to the capital and credit markets on reasonable terms when needed. However, there can be no assurance that significant changes in economic conditions, disruptions in the capital and credit markets, or other unforeseen events will not materially affect their ability to execute their expected operating, capital, or financing plans.

• Ameren expects its cash used for currently planned capital expenditures and dividends to exceed cash provided by operating activities over the next several years. As part of its funding plan for capital expenditures, Ameren is using newly-issued shares of common stock to satisfy requirements under the DRPlus and employee benefit plans and expects to continue to do so through at least 2028. Additionally, Ameren has an ATM program under which Ameren may offer and sell from time to time common stock, which includes the ability to enter into forward sales agreements, subject to market conditions and other factors. As of September 30, 2024, Ameren had multiple forward sale agreements that could be settled under the ATM program with various counterparties relating to 4.7 million shares of common stock. Ameren expects to settle approximately $230 million of the forward sale agreements with physical delivery of 2.9 million shares of common stock by December 31, 2024. Including issuances under the DRPlus and employee benefit plans, Ameren plans to issue approximately $300 million of equity in 2024 and approximately $600 million of equity each year from 2025 to 2028. As of September 30, 2024, Ameren had approximately $615 million of common stock available for sale under the ATM program, which takes into account the forward sale agreements in effect as of September 30, 2024. The Ameren Companies expect their equity to total capitalization to support solid investment-grade credit ratings. Ameren Missouri and Ameren Illinois expect to fund cash flow needs through debt issuances, cash provided by operating activities, and/or capital contributions from Ameren (parent).

• The IRA was enacted in August 2022, and includes various income tax provisions, among other things. The law extends federal production and investment tax credits for projects beginning construction through 2024 and allows for a 10% adder to the production and investment tax credits for siting projects at existing energy communities as defined in the law, which includes sites previously used for coal-fired generation. The law also creates clean energy tax credits for projects placed in service after 2024. The clean energy tax credits will apply to renewable energy production and investments, along with certain nuclear energy production, and will be phased out beginning in 2033, at the earliest. The phase-out is triggered when greenhouse gas emissions from the electric generation industry are reduced by at least 75% from the annual 2022 emission rate or at the beginning of 2033, whichever is later. The law allows for transferability to an unrelated party for cash of up to 100% of certain tax credits generated after 2022. In addition, the new law imposes a 15% minimum tax on adjusted financial statement income, as defined in the law, for corporations whose average annual adjusted financial statement income exceeds $1 billion for three consecutive preceding tax years effective for tax years beginning after December 31, 2022. Once a corporation exceeds this three-year average annual adjusted financial statement income threshold, it will be subject to the minimum tax for all future tax years. Additional regulations, interpretations, amendments, or technical corrections to or in connection with the IRA have been and are expected to be issued by the IRS or United States Department of Treasury, which may impact the timing of when the 15% minimum tax becomes applicable for Ameren as discussed below.

• Pursuant to the IRA discussed above, Ameren expects to transfer production tax credits generated by Ameren Missouri’s High Prairie Renewable and Atchison Renewable energy centers, as well as production or investment tax credits related to the solar facilities included in Ameren Missouri’s 2023 IRP discussed above, to unrelated third parties from 2024 to 2028.

• In April 2023, the IRS issued guidance providing a safe harbor method of accounting for the capitalization or deduction of certain expenditures to maintain, repair, replace, or improve natural gas distribution property. Ameren expects to adopt this guidance for the 2024 tax year, but is still evaluating its potential impact.

• In June 2024, the IRS issued a series of private letter rulings to another taxpayer which provided guidance on applying IRS normalization rules to the calculation of tax benefits related to net operating loss carryforwards. The rulings concluded that for ratemaking purposes, net operating loss carryforwards should be reflected on a separate company basis and should not be reduced by payments received for the utilization of losses by other affiliates under a tax allocation agreement. While a private letter ruling issued to another taxpayer may not be relied on as precedent, Ameren Missouri, Ameren Illinois, and ATXI are evaluating this guidance and are addressing potential impacts of the private letter rulings with the MoPSC, ICC, and FERC. For Ameren Illinois and ATXI, these impacts could result in material reductions to their regulatory liabilities related to excess deferred taxes resulting from the TCJA. For Ameren Missouri and Ameren Illinois, these impacts could result in material increases to their accumulated deferred income tax assets for ratemaking purposes, which would result in overall increases to their rate bases. Ameren Missouri, Ameren Illinois, and ATXI will record the impacts, if any, upon further evaluation with their respective regulatory commissions.

• As of September 30, 2024, Ameren had $113 million in tax benefits from federal and state income tax credit carryforwards, $41 million in tax benefits from state net operating loss carryforwards, and $24 million in tax overpayments, refunds, and receivables, which will be utilized in future periods. Future expected income tax payments are based on expected taxable income, available income tax credit and net operating loss carryforwards, and current tax law. Expected taxable income is affected by expected capital expenditures, when property, plant, and equipment is placed in-service or retired, and the timing of regulatory reviews, among other things. Based on preliminary calculations, Ameren does not expect to be subject to the 15% minimum tax on adjusted financial statement income imposed by the IRA through 2028. Ameren expects annual federal income tax payments to be immaterial through 2028.

The above items could have a material impact on our results of operations, financial position, and liquidity. Additionally, in the ordinary course of business, we evaluate strategies to enhance our results of operations, financial position, and liquidity. These strategies may include acquisitions, divestitures, opportunities to reduce costs or increase revenues, and other strategic initiatives to increase Ameren’s shareholder value. We are unable to predict which, if any, of these initiatives will be executed. The execution of these initiatives may have a material impact on our future results of operations, financial position, or liquidity.

REGULATORY MATTERS

See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report.