Ameren (AEE) 10-K risk factor changes: FY2024 vs FY2023

In the planning and management of our operations, we must address the effects of existing and proposed laws and regulations and potential changes in our regulatory frameworks, including [added: reinterpretation of such regulations, as well] initiatives by federal and state legislatures, RTOs, utility regulators, and taxing authorities, and actions by local jurisdictions that may affect the constructing or siting of facilities.

Significant changes in the nature of the regulation of our businesses, including expiration or discontinuation of, or significant changes to, existing regulatory mechanisms, [added: and the current federal administration’s approach to United States energy policy and resultant changes in regulatory enforcement priorities, and/or evolving interpretations of existing regulatory requirements,] could require changes to our business [removed: planning] [added: planning, strategy] and management of our businesses and could adversely affect our results of operations, financial position, and liquidity.

From time to time, our regulators may approve [removed: trackers, riders,] [added: riders] or other recovery mechanisms that allow electric or natural gas rates to be adjusted without a traditional regulatory rate review.

Ameren Missouri’s electric and natural gas utility rates established in those proceedings [added: are based on historical costs, revenues, and sales volumes.]

Effective for rates [removed: beginning] in 2024 through at least 2027, Ameren Illinois’ electric distribution rates [removed: will be] [added: have been] established through an MYRP as discussed in the following risk factor.

Ameren Missouri and Ameren Illinois, and the utility industry generally, have an increased need for cost [removed: recovery,] [added: recovery and to earn a return on investments,] primarily driven by capital investments, which is likely to continue in the future.

[removed: Beginning in] [added: In] 2024 through at least 2027, electric distribution rates for Ameren Illinois are established through an MYRP, which are subject to ongoing regulatory and judicial proceedings and associated risks, and are subject to a reconciliation cap.

The CEJA resulted in changes to the regulatory framework applicable to Ameren Illinois’ electric distribution business by giving Ameren Illinois the option to file an MYRP with the ICC or establish [removed: future] rates through a traditional regulatory rate review, among other things.

Under the MYRP, Ameren Illinois [removed: will] [added: is allowed to] reconcile its actual [added: electric distribution] revenue requirement, as adjusted for certain cost variations, to [added: the] ICC-approved [removed: electric distribution service rates] [added: revenue requirement] on an annual basis, subject to a reconciliation cap.

Ameren Illinois’ existing riders [removed: remain effective and electric distribution service revenues] continue to be [removed: decoupled from sales volumes] [added: effective] under the MYRP.

[removed: Also, in January 2024,] Ameren Illinois [added: has] filed an appeal of the [removed: December 2023 ICC order and the partial denial of Ameren Illinois’ request] [added: ICC-determined ROE] for [removed: rehearing] [added: 2024 through 2027] to the Illinois Appellate Court for the Fifth Judicial District.

[added: Failure] to [removed: which] [added: limit capital expenditures and operation and maintenance expenses to amounts that] maintain revenue requirements under the reconciliation cap limit would adversely affect Ameren’s and Ameren Illinois’ results of operations, financial position, and liquidity.

[removed: These performance metrics include improvements in service reliability in both the frequency and duration of outages, a reduction in peak loads, an increased percentage of] spend with diverse suppliers, a reduction in disconnections for certain customers, and improved timeliness in response to customer requests for interconnection of distributed energy resources.

As a result of the election to use the PISA, [removed: effective in 2024,] Ameren Missouri’s electric service business is subject to a limitation on increasing the annual revenue requirement due to the inclusion of incremental PISA deferrals in the revenue requirement.

Pursuant to a Missouri [removed: law that became effective in August 2022,] [added: law,] 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.

The limitation [removed: will be] [added: is] effective for revenue requirements approved by the MoPSC after January 1, 2024.

Such environmental laws [removed: address] [added: regulate] air emissions; [removed: discharges to] [added: protect] water bodies; [added: manage] the [removed: storage,] handling and disposal of hazardous substances and waste materials; siting and land use requirements; and potential ecological impacts.

Environmental regulations have a significant impact on the electric utility industry and compliance with these regulations could be costly for Ameren Missouri, which operates coal-fired [removed: power plants.][added: and natural gas-fired energy centers.]

As of December 31, [removed: 2023,] [added: 2024,] Ameren Missouri’s coal-fired energy centers represented [removed: 8%] [added: 6%] and [removed: 16%] [added: 11%] of Ameren’s and Ameren Missouri’s rate base, respectively.

[removed: Regulations] [added: Compliance obligations] under the Clean Air Act [removed: that apply to the electric utility industry] include the NSPS, the [removed: CSAPR, the] MATS, [added: emission allowance programs] and the [added: CSAPR, and the] National Ambient Air Quality Standards, which are subject to periodic review for certain pollutants.

Regulations implementing the Clean Water Act govern [removed: both intake and discharges of water,] [added: potential impacts from our operations on water bodies including wetlands subject to the Act,] as well as evaluation of the ecological and biological impact of those [removed: operations, and could require modifications to water intake structures or more stringent limitations on wastewater discharges.][added: operations.]

[removed: The] [added: Coal-fired energy centers must comply with] management and disposal [removed: of] [added: requirements for] coal ash [removed: is regulated] under the Resource Conservation and Recovery Act and [added: federal regulations known as] the CCR [removed: Rule, which require the closure of surface impoundments at Ameren Missouri’s coal-fired energy centers.][added: Rule.]

[removed: Related to this matter,] [added: In addition,] in [removed: November 2023, Ameren Missouri petitioned] [added: June 2024,] the MoPSC [removed: for] [added: issued] a financing order [removed: to authorize] [added: authorizing] the issuance of securitized utility tariff bonds [added: by a wholly owned, special purpose subsidiary of Ameren Missouri] to finance [removed: $519] [added: approximately $476] million of costs related to the [removed: planned] accelerated retirement of the Rush Island Energy Center, which [removed: includes] [added: included] the [removed: expected] remaining unrecovered net plant balance associated with the [removed: facility.][added: facility, among other costs.]

Ameren Missouri [removed: requested to] [added: will] collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance.

If [removed: Ameren Missouri is not allowed to recover Rush Island Energy Center costs through securitization or if] future [removed: rate reviews] [added: regulatory proceedings] result in revenue reductions based on Ameren Missouri’s prior actions that resulted in the adverse ruling [removed: discussed above,] [added: 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 [removed: May 2023,] [added: April 2024,] the EPA issued a [removed: new proposed] [added: final] rule that [removed: would set] [added: sets] CO2 emission standards for [removed: new and] existing [removed: fossil-fuel-fired] [added: coal-fired and new natural gas-fired] power plants based on the [added: emissions expected from] adoption of carbon capture [removed: technology,] [added: technology and/or] natural gas [removed: co-firing, and] co-firing [removed: hydrogen fuel to reduce emissions.][added: for coal-fired power plants and]

[removed: If the proposed rule were adopted, the affected fossil-fuel-fired] [added: Affected] power plants [removed: would be] [added: are] required to comply with the rule through a phased-in approach or retire.

Ameren and Ameren Missouri [removed: cannot predict] [added: are monitoring] the [removed: results of any such] [added: legal] challenges [removed: or potential] [added: and assessing the] impacts of [removed: any such regulations] [added: the final rule and, at this time, cannot predict the final impacts] on their results of operations, financial position, and [removed: liquidity until final regulations are adopted and the merits of such legal challenges are determined.][added: liquidity.]

[added: Currently as required by the CEJA,] Ameren Missouri's natural gas-fired energy centers in Illinois are subject to annual limits on emissions, including CO2 and NOx.

Capital expenditures and costs to comply with future legislation or regulations [removed: might] [added: could] result in Ameren Missouri closing coal-fired energy centers earlier than planned.

We are subject to business and financial risks related to the impact of climate change legislation, regulation, and emission reduction [removed: goals.][added: initiatives.]

There is [removed: increasing] concern and activism among various external stakeholders, both nationally and internationally, about climate change, including public concerns about the potential environmental impacts from the combustion of fossil fuels, as well as pressure from public interest groups regarding limiting the use of natural gas.

Also, state and local authorities have proposed restrictions on the use of natural gas, and the ICC [removed: has initiated] [added: is conducting] a future of gas proceeding to explore issues involved with decarbonization of the natural gas distribution system in the state of Illinois.

Further, federal, state, and local authorities, including the United States Congress, have considered initiatives to further restrict greenhouse gases to address global climate [removed: change.][added: change, and the EPA previously announced plans to implement new climate change programs, including regulation of greenhouse gas emissions from the utility industry.]

Additionally, international agreements [added: have in the past, and] could [added: again,] lead to future federal or state legislation or regulations.

Excessive costs to comply with future legislation or regulations related to climate change might force Ameren Missouri to close [removed: some] [added: its remaining] coal-fired energy centers earlier than planned, which could lead to possible loss on abandonment and reduced revenues.

Ameren is targeting net-zero carbon emissions by 2045, as well as a 60% reduction by 2030 and an 85% reduction by 2040 based on 2005 [removed: levels.][added: levels in a safe, reliable, and affordable manner.]

Ameren’s goals include both [added: 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.

Achievement of these [removed: goals] [added: targets] is dependent on many factors, including the pace and extent of development and deployment of low- to zero-carbon energy technologies and carbon capture technologies, [removed: and] the cost of those [removed: technologies;] [added: technologies, and support of such technologies by regulators;] natural gas prices; new transmission infrastructure; the ability to maintain system reliability during [added: and after] the transition to clean energy generation; and constructive energy and economic policies, including those that address investment in energy infrastructure, global climate change, incentives for clean energy technologies, and environmental regulations.

The strategy to achieve these goals also relies on continuing to pursue a diverse [removed: portfolio] [added: portfolio,] including low-carbon and carbon-free resources and energy-efficiency resources; continuing to participate in efforts to help advance the development of technologies such as carbon [removed: capture, utilization,] [added: capture] and sequestration; the use of hydrogen fuel for electric production and energy storage, next generation nuclear, and large-scale long-cycle battery energy storage; and constructively engaging with legislators, regulators, investors, customers, and other stakeholders to support outcomes leading to a net-zero future.

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The securitized tariff bonds were issued in December 2024.

The financing order also included 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 14 – Commitments and Contingencies under Part II, Item 8, of this report, however, claims regarding such actions could be considered in future regulatory proceedings.

These performance metrics include improvements in service reliability in both the frequency and duration of outages, a reduction in peak loads, an increased percentage of

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Implementation of the Clean Air Act and the Clean Water Act requirements typically occurs through the issuance of permits by state regulators or resource agencies, and capital expenditures associated with compliance could be significant.

Surface impoundments at Ameren Missouri’s coal-fired energy centers are subject to closure and groundwater monitoring requirements and the implementations of corrective measures if necessary.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

carbon capture technology for new natural gas-fired power plants.

Compliance with the new rule could be required as early as 2030 for certain existing coal-fired power plants and 2032 for certain new natural gas-fired power plants.

In December 2024, the United States Court of Appeals for the District of Columbia Circuit heard arguments from various stakeholders including the EPA, environmental organizations, state attorney generals, and industry groups regarding the legal merits of the final rule.

In February 2025, the EPA requested that the appellate court suspend the case for 60 days and not issue an opinion so the EPA can decide how to proceed.

Ameren and Ameren Missouri estimate capital expenditures of approximately $580 million may be necessary to comply with the final rule assuming it is not revised or overturned.

In accordance with the new presidential administration’s approach to United States energy policy, in January 2025, the United States withdrew from the Paris Agreement.

The current federal administration is expected to review, and has already revised, compliance requirements under a number of federal environmental regulatory programs; however, differences in energy policy priorities adopted by future federal administrations could result in additional greenhouse gas reduction requirements in the United States.

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- inability to operate wind generation facilities at full capacity resulting from requirements to protect natural resources, including wildlife, or other conditions limiting full capacity, such as the 2024 collapse of three turbines at the High Prairie Energy Center; pending the results of an ongoing investigation, approximately 90% of the turbines of the High Prairie Energy Center remain idle and the timing and costs necessary to return the energy center to full capacity are uncertain;

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maintenance expense.

Forecasted energy demand from potential new customers and electrification might not be realized.

The Ameren Companies have experienced minimal growth in energy demand for the past two decades.

Recent industry projections reflect the potential for significant growth in energy demand over the next decade, primarily arising from data centers to support artificial intelligence and further augmented by onshoring and electrification of manufacturing and an increase in transportation electrification.

The Ameren Companies may or may not experience energy demand growth depending on the decisions of potential new customers about whether to locate their operations within our service territories.

If new customers elect to locate operations within our service territories, the Ameren Companies may not be able to provide the necessary electric service within the time periods required by those customers.

The Ameren Companies may need to accelerate new generation build within current plans, and construct or obtain new generation sources and expand transmission and distribution facilities that are not currently within their plans.

The Ameren Companies may not be able to plan, receive regulatory approvals, and execute those plans in a timely manner.

Future demand from these customers may not be realized at the current projected pace as a result of increased efficiency in computing, and these new customers may be transitory and exit our service territory.

Significant uncertainty exists regarding future increases in energy demand within the Ameren Companies’ service territory, and whether and how the Ameren Companies will construct or obtain the assets necessary to timely serve that additional demand.

The payments related to the minimum tax by Ameren

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In addition, interpretations, regulations, amendments, or technical corrections that affect the amount and timing of income tax payments, credits available, or the transferability of production and investment tax credits could adversely affect our liquidity.

Higher than expected inflation levels could continue to put pressure on the prices of labor, services, materials and supplies, and other costs.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

increased use of distributed generation by our customers.

In addition, the increasingly widespread adoption of artificial intelligence technologies, including generative artificial intelligence, may increase cyber attacks and other operational, legal, privacy, and reputational risks in our industry and worldwide.

These factors include depressed economic conditions, a recession,

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

are primarily based on historical costs, revenues, and sales volumes.

In December 2023, the ICC issued an order in Ameren Illinois' MYRP proceeding, approving revenue requirements for electric distribution service for 2024, 2025, 2026, and 2027 of $1,162 million, $1,210 million, $1,242 million, and $1,255 million, respectively.

These revenue requirements were established under an alternative methodology which used Ameren Illinois’ previously approved 2022 year-end rate base since the order rejected the Grid Plan that was filed by Ameren Illinois as a part of the MYRP proceeding.

The ICC concluded that the proposed Grid Plan did not meet certain statutory requirements and directed Ameren Illinois to file a revised Grid Plan within three months.

Ameren Illinois expects to file a revised Grid Plan with the ICC in March 2024, and also expects to file a request to update the associated MYRP revenue requirements for 2024 through 2027 in the first half of 2024.

The 2022 year-end rate base will remain in effect through 2027, unless subsequently changed by the ICC in the rehearing discussed below or if approval of a revised Grid Plan results in an update of each year’s revenue requirement.

In January 2024, Ameren Illinois filed a request for rehearing of the ICC's December 2023 order.

The filing contended that the use of the 2022 year-end rate base for each year of the MYRP, until a revised Grid Plan is approved, is unlawful and not in compliance with the CEJA.

In addition, the filing requested the ICC revise the order to include an allowed ROE of at least 9.82% for each year of the MYRP and include a base level of investments to maintain grid reliability in each year of the MYRP, among other things.

In January 2024, the ICC partially denied Ameren Illinois’ rehearing request by denying Ameren Illinois’ request regarding the allowed ROE, and granting Ameren Illinois’ request to consider whether it is appropriate to use the 2022 year-end 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.

Additionally, the scope of the rehearing will include a review of certain operations and maintenance expenses in each year of the MYRP.

In February 2024, Ameren Illinois filed its request in the rehearing proceeding, which proposed updated revenue requirements of $1,214 million, $1,300 million, $1,371 million, and $1,420 million, for 2024, 2025, 2026, and 2027, respectively.

An ICC decision in this rehearing is expected by late June 2024.

The court is under no deadline to address the appeal.

Ameren Illinois cannot predict the ultimate outcome of the revised Grid Plan filing, its request to update the associated MYRP revenue requirements for 2024 through 2027, the rehearing proceeding, or the appeal to the Illinois Appellate Court for the Fifth Judicial District.

Failure to limit capital expenditures and operation and maintenance expenses to amounts

Ameren Illinois’ QIP expired in December 2023, which will subject Ameren Illinois to increased regulatory lag with respect to certain natural gas infrastructure investments.

In addition, reconciliation hearings to determine the accuracy and prudence of natural gas capital investments recovered under the QIP are still ongoing.

The QIP expired in December 2023.

Previously, it provided Ameren Illinois with recovery of, and a return on, qualifying natural gas infrastructure investments that were placed in service between regulatory rate reviews.

Infrastructure investments under the QIP earned a return at the applicable WACC.

As a result of the expiration of the QIP, Ameren Illinois is subject to increased regulatory lag on its natural gas infrastructure investments that are placed in service between regulatory rate reviews, which could adversely affect Ameren’s and Ameren Illinois’ investment plans and results of operations, financial position, and liquidity.

In addition, reconciliation hearings to determine the accuracy and prudence of natural gas capital investments recovered under the QIP from 2020 to 2023 are still ongoing.

In October 2023, the Illinois Attorney General’s office challenged the recovery of capital investments that were made during 2020, alleging that the ICC should disallow approximately $53 million in natural gas capital investments as improper and imprudent, providing a potential over-recovery of approximately $3 million in 2020.

In October 2023, the ICC staff filed testimony that supports the prudence and reasonableness of the capital investments made during 2020.

Ameren Illinois’ 2020 QIP rate recovery request under review by the ICC was within the rate increase limitations allowed by law.

The ICC is under no deadline to issue an order in this proceeding.

Ameren Illinois cannot predict the ultimate outcome of this regulatory proceeding.

Depending upon the scope of modifications ultimately required by state regulators, capital expenditures associated with these modifications could be significant.

In January 2011, the United States Department of Justice, on behalf of the EPA, filed a complaint against Ameren Missouri in the United States District Court for the Eastern District of Missouri alleging that projects performed in 2007 and 2010 at the coal-fired Rush Island Energy Center violated provisions of the Clean Air Act and Missouri law.

In January 2017, the district court issued a liability ruling against Ameren Missouri and, in September 2019, entered a remedy order that required Ameren Missouri to install a flue gas desulfurization system at the Rush Island Energy Center and a dry sorbent injection system at the Labadie Energy Center.

Following an appeal from Ameren Missouri, in August 2021, the United States Court of Appeals for the Eighth Circuit affirmed the liability ruling and the district court’s remedy order as it related to the installation of a flue gas desulfurization system at the Rush Island Energy Center, but reversed the order as it related to the installation of a dry sorbent injection system at the Labadie Energy Center.

In September 2023, the district court granted Ameren Missouri’s request to modify the remedy order to allow the retirement of the Rush Island Energy Center in advance of its previously expected useful life in lieu of installing a flue gas desulfurization system.

In its amended remedy order, the district court established an October 15, 2024 retirement date and, in the interim, authorized Ameren Missouri to operate the energy center as directed by the MISO.

The United States Department of Justice is seeking an order from the district court providing for additional mitigation relief.

Ameren Missouri could be required to implement mitigation relief measures, the costs of which could be material and which Ameren Missouri would not expect to recover.

Ameren Missouri is challenging such mitigation claims, noting that the scope of any such potential additional mitigation relief should be limited by the August 2021 court of appeals decision and offset by emission reductions resulting from the accelerated retirement of the Rush Island Energy Center.

The MISO designated the energy center as a system support resource in 2022 and concluded that certain reliability mitigation measures, including transmission upgrades, should occur before the energy center is retired.

The Rush Island Energy Center began operating as a system support resource on September 1, 2022.

Discussion regarding our financial condition and results of operations for the year ended December 31, [removed: 2021,] [added: 2022,] including comparisons with the year ended December 31, [removed: 2022,] [added: 2023,] is included in Item 7 of our Form 10-K for the year ended December 31, [removed: 2022.][added: 2023.]

| We invest in rate-regulated energy infrastructure and seek to earn competitive returns on our investments. We seek to make prudent investments that benefit our customers. The goal of these investments is to maintain and enhance the reliability of our services, develop and deliver cleaner sources of energy, create economic development opportunities in our region, and provide customers with more options and greater control over their energy usage, among other things. By prudently investing in our businesses, we believe that we deliver superior value to both customers and shareholders. | | | | | | | | | We seek to partner with our stakeholders, including our customers, [added: communities,] regulators, federal and state legislators, and RTOs, to enhance our regulatory frameworks and advocate for responsible energy and economic policies for the benefit of our [removed: customers] [added: customers, communities,] and shareholders. We believe enhancing our regulatory frameworks is important to drive investment in our business segments, earn competitive returns on those investments, and realize timely recovery of our costs with the benefits accruing to both customers and shareholders. | | | | | | | | | Utilizing a continuous improvement mindset, we seek to optimize operating performance for the benefit of our customers. We remain focused on disciplined cost management and strategic capital allocation. We align our overall spending, both operating and capital, with economic conditions and with the frameworks established by our regulators. We focus on minimizing the gap between allowed and earned ROEs and allocating capital resources to business opportunities that we expect will provide the most benefit to our customers and offer the most attractive risk-adjusted return potential. | | |

| Rate Base ($ in billions)(a) | | | | | | | | | Regulatory Frameworks(c) | | | | | | | | | [removed: Improved Reliability(f)] [added: Electric Customer Rates(f)] | | |

| ] [added: 2024 - 1.gif](https://www.sec.gov/Archives/edgar/data/1002910/000100291025000055/aee-20241231_g6.gif)] | | | | | | | | | Segment | | | Regulatory Framework | | | | | | [removed: ] [added: ] | | |

| | | | Ameren Transmission | | | *Formula ratemaking [added: with initial rates based on a future test year] Allowed ROE of [removed: 10.52%*] [added: 10.48%*] | | | | | | | | | | | | | | |

| | | | Ameren Illinois Electric Distribution | | | *Future test year ratemaking under an MYRP(d)* [added: *and RBA*] *Allowed ROE of 8.72%(e)* | | | | | | | | | | | | | | |

| (a)Reflects year-end rate base except for Ameren Transmission, which is average rate base. Ameren Illinois Electric Distribution excludes electric energy-efficiency rate base. (b)Compound annual growth rate. (c)As of January [removed: 2024. (d)In January 2024, Ameren] [added: 2025. (d)Ameren] Illinois filed [added: appeals of the December 2023 and June 2024 orders, and intends to file] an appeal of the December [removed: 2023] [added: 2024] ICC [removed: order] [added: order,] in its MYRP proceeding. For more information on the MYRP proceeding, see Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report. (e)Ameren Illinois’ formula ratemaking framework related to energy-efficiency investments uses an allowed ROE of the annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points, subject to performance standards discussed in Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report. [removed: (f)As measured by Ameren Missouri’s] [added: (f)Average residential electric prices. Source: Edison Electric Institute, ‘Typical Bills] and [removed: Ameren Illinois’ System] Average [removed: Interruption Frequency Index.] [added: Rates Report’ for the 12 months ended June 30, 2024.] | | | | | | | | | | | | | | | | | | | | |

In [removed: February] 2024, [removed: Ameren Missouri,] the MoPSC [removed: staff, and the MoOPC filed a nonunanimous stipulation and agreement requesting the MoPSC approve Ameren Missouri’s requests for] [added: issued orders approving requested] CCNs for the Split Rail, Vandalia, [removed: and] Bowling [removed: Green] [added: Green, and Cass County] solar projects.

[removed: The proposed plan] [added: In November 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement for Ameren Missouri’s MEEIA 2025 plan, which] includes a portfolio of customer energy-efficiency [added: and demand response] programs, along with the continued use of the MEEIA rider, which allows Ameren Missouri to collect [removed: from, or refund to,] [added: from] customers [removed: any difference in] [added: its] actual MEEIA program [removed: costs and] [added: costs,] related lost electric [removed: margins] [added: revenues,] and [removed: the amounts collected from customers.][added: performance incentives.]

In addition, [removed: Ameren Missouri requested] [added: the order approved] performance incentives applicable to each plan year to earn revenues by achieving certain [removed: customer energy-efficiency savings and target] spending [added: and demand response] goals.

If 100% of the goals are [removed: achieved,] [added: achieved in 2025, 2026, and 2027,] Ameren Missouri would earn performance incentive revenues [removed: totaling $56 million over the three-year plan.][added: of $5 million, $5 million, and $2 million, respectively.]

In [removed: November 2023, Ameren Missouri petitioned] [added: June 2024,] the MoPSC [removed: for] [added: issued] a financing order [removed: to authorize] [added: authorizing] the issuance of securitized utility tariff bonds [added: by AMF] to finance [removed: $519] [added: $476] million of costs related to the [removed: planned] accelerated retirement of the Rush Island Energy Center, which [removed: includes] [added: included] the [removed: expected] remaining unrecovered net plant balance associated with the [removed: facility.][added: facility, among other costs.]

Ameren Missouri [removed: requested to] [added: will] collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance.

[removed: However, the] [added: The] MoPSC [removed: staff claimed] [added: did not make a determination regarding the prudency of] Ameren [removed: Missouri’s] [added: Missouri's] prior actions that resulted in the adverse ruling in the NSR and Clean Air Act [removed: Litigation] [added: litigation] discussed in Note 14 – Commitments and Contingencies under Part II, Item 8, of this report, [removed: were imprudent and recommended that the impact of those] [added: however, claims regarding such] actions [removed: on customers] [added: could] be considered in future [removed: rate reviews.][added: regulatory proceedings.]

If [removed: Ameren Missouri is not allowed to recover Rush Island Energy Center costs through securitization or if] future [removed: rate reviews] [added: 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 [removed: Litigation,] [added: litigation,] it could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri.

In February [removed: 2024,] [added: 2025,] 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 [removed: 2024.][added: 2025.]

Investments under the plan are expected to total approximately [removed: $12.4] [added: $16.2] billion over the five-year period from [removed: 2024] [added: 2025] through [removed: 2028,] [added: 2029,] with expenditures largely recoverable under the PISA.

[removed: Ameren Missouri’s] [added: The] Smart Energy Plan excludes investments in its natural gas distribution business, as well as removal costs, net of salvage.

In December 2023, the ICC issued an order in Ameren Illinois' MYRP [removed: proceeding,] [added: 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 [added: December 2024] order became effective in [removed: January] [added: December] 2024.

[added: In March 2024, pursuant to the December 2023 ICC order discussed above,] Ameren Illinois [removed: expects to file] [added: filed] a revised Grid Plan [removed: with the ICC in March 2024,] and [removed: also expects to file] a [removed: request] [added: revised MYRP] to update the [removed: associated MYRP] [added: requested] revenue requirements for 2024 through [removed: 2027 in the first half of 2024.][added: 2027.]

The December 2023 order adopted an alternative methodology to establish a rate base and revenue requirements for the years 2024 through [removed: 2027,] [added: 2027] using [removed: the] [added: Ameren Illinois’ previously approved] 2022 year-end rate [removed: base approved by the ICC in its 2022 electric distribution service revenue requirement reconciliation adjustment order discussed below.][added: base.]

In January 2024, [added: the ICC denied] Ameren [added: Illinois’ rehearing request, and Ameren] Illinois filed [removed: a request] [added: an appeal with the Illinois Appellate Court] for [removed: rehearing of] the [removed: ICC's December 2023 order.][added: Fifth Judicial District.]

In January 2024, the ICC partially denied [removed: Ameren Illinois’] [added: a] rehearing [removed: request] [added: requested] by [removed: denying] Ameren [removed: Illinois’ request regarding] [added: Illinois to revise] the allowed [removed: ROE,] [added: ROE in the December 2023 order] and [removed: granting] [added: granted] Ameren Illinois’ [added: rehearing] request to [removed: consider whether it is appropriate to use] [added: reconsider] the [removed: 2022 year-end] 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.

[removed: Also, in January 2024,] Ameren Illinois [removed: filed] [added: intends to file] an appeal of the [added: ICC’s] December [removed: 2023 ICC] [added: 2024] order [removed: and the partial denial of Ameren Illinois’ request for rehearing] to the Illinois Appellate Court for the Fifth Judicial District.

The court is under no deadline to address the [added: appeal and Ameren Illinois cannot predict the ultimate outcome of the] appeal.

In [removed: November 2023,] [added: December 2024,] the ICC issued an order approving Ameren Illinois’ [removed: 2022] [added: 2023] electric distribution service revenue requirement reconciliation adjustment filing.

This order approved a reconciliation adjustment of [removed: $110] [added: $158] million, which reflected Ameren Illinois’ actual [removed: 2022] [added: 2023] recoverable costs, year-end rate base of [removed: $3.9] [added: $4.2] billion, and [removed: a] capital structure composed of 50% common equity.

The approved reconciliation adjustment will be collected from customers in [removed: 2024.][added: 2025.]

In [removed: addition,] [added: December 2024, the ICC issued an order approving] Ameren [removed: Illinois will file its] [added: Illinois’] 2023 electric distribution service revenue requirement reconciliation [removed: with the ICC by May 2024, which will reflect its 2023 year-end rate base.][added: adjustment filing.]

The [removed: 2023 reconciliation adjustment, if] approved [removed: by the ICC,] [added: reconciliation adjustment] will be collected from customers in 2025.

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 a reversal of the approximately $93 million reduction of planned distribution and [removed: transmission capital investments included in the order, among other things.]

[removed: In January] [added: Subsequently, in August] 2024, the ICC denied [removed: Ameren Illinois’] [added: the] rehearing request.

[removed: Subsequently, in January 2024,] Ameren Illinois [removed: filed] [added: intends to file] an appeal of the [removed: November 2023 ICC] [added: ICC’s December 2024] order and [added: update] the [removed: January] [added: appeal filed in September] 2024 [removed: ICC denial of Ameren Illinois’ request for rehearing] to the Illinois Appellate Court for the Fifth Judicial [removed: District.][added: District as discussed above.]

[added: The appellate court is under no deadline to address the appeal, and] Ameren Illinois cannot predict the ultimate outcome of [removed: this] [added: the] appeal.

In November [removed: 2023,] [added: 2024,] the ICC issued an order in Ameren Illinois’ annual update filing that approved electric customer energy-efficiency rates of [removed: $100] [added: $126] million beginning in January [removed: 2024,] [added: 2025,] which represents an increase of [removed: $24] [added: $26] million from [removed: 2023] [added: 2024] rates.

[removed: The] [added: This] order was based on a projected [removed: 2024] [added: 2025] year-end rate base of [removed: $394] [added: $434] million.

In [removed: July] 2022, the MISO approved the first tranche of projects under the [removed: first phase of the] roadmap.

Related to these projects, Ameren [removed: expects to begin] [added: began] substation upgrades in [added: 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 February 2024, Ameren Illinois and ATXI filed a request for a [removed: CCN] [added: CCN, among other things,] with the ICC related to the portion of the MISO long-range transmission projects [removed: discussed above that are expected to be constructed] [added: they will construct] within the ICC’s jurisdiction.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

Ameren Missouri retired the Rush Island Energy Center on October 15, 2024.

In December 2024, the United States District Court for the Eastern District of Missouri issued an order resolving all outstanding claims in this case.

The order requires 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 December 31, 2024, Ameren and Ameren Missouri recorded liabilities of $64 million and charges of $59 million in 2024 related to the cost of these programs.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

In June 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for electric service.

In February 2025, Ameren Missouri filed an updated electric rate increase request 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 $13.9 billion, and a test year ended March 31, 2024, with certain pro-forma adjustments through the true-up date of December 31, 2024.

In February 2025, the MoPSC staff recommended an increase to Ameren Missouri's annual electric service revenues of $384 million based on a 9.74% ROE, a capital structure composed of 52% common equity, and a rate base of $13.9 billion.

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.

The securitized tariff bonds were issued in December 2024.

The financing order also included a determination that the decision to retire the Rush Island Energy Center was reasonable and prudent.

Ameren Missouri acquired the Cass County, Boomtown, and Huck Finn solar projects in June 2024, September 2024, and October 2024, respectively, and placed the assets of the projects, totaling $1 billion, in service in December 2024.

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 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.

Ameren Missouri intends to invest $51 million annually in 2025 and 2026 and $22 million in 2027 for customer energy-efficiency and demand response programs.

Ameren Missouri’s Smart Energy Plan includes approximately $1 billion in capital expenditures that may be necessary to comply with regulations issued by the EPA in 2024 relating to CO2 emissions and MATS, if such regulations are not revised or overturned.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

transmission capital investments included in the order, among other things.

In January 2025, the appellate court ruled on the appeal filed by Ameren Illinois.

In that ruling, the court reversed a reduction of planned transmission capital investments of $48 million, but affirmed the ICC-approved 9.44% ROE and the remaining reduction of planned distribution capital investments.

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.

In June 2024, the ICC issued an order on Ameren Illinois’ rehearing request approving revenue requirements for electric distribution services for 2024 through 2027.

New rates became effective in late June 2024 and remained effective through late December 2024, when new rates became effective pursuant to the December 2024 ICC order discussed below.

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.

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.

In January 2025, Ameren Illinois filed a request for rehearing of the ICC’s December 2024 order to revise the allowed ROE and to include an asset associated with other postretirement benefits in the rate base, among other things.

Subsequently, in February 2025, the ICC denied the rehearing request.

In 2024, Ameren Illinois took prudent steps to align its operations with the December 2023 and June 2024 ICC orders, while continuing to ensure safe and adequate service was maintained.

The request is based on a 10.7% ROE, a capital structure composed of 52% common equity, and a rate base of $3.3

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

billion.

Ameren Illinois used a 2026 future test year in this proceeding.

A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in December 2025.

Ameren Missouri’s subsidiaries were created for the ownership of renewable generation projects.

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

In June 2023, the MoPSC issued an order that resulted in an increase of $140 million to Ameren Missouri’s annual revenue requirement for electric retail service.

The approved revenue requirement was based on infrastructure investments as of December 31, 2022, and included an extension of the depreciable lives of the Sioux Energy Center’s assets from 2028 to 2030.

The order did not explicitly specify an ROE, capital structure, or rate base.

The order provides for the continued use of the FAC and trackers for pension and postretirement benefits, uncertain income tax positions, certain excess deferred income taxes, and renewable energy standard compliance costs that the MoPSC previously authorized in earlier electric rate orders, as well as the use of an electric property tax tracker.

It also includes a tracker for the utilization of production and investment tax credits or proceeds from the sale of such tax credits allowed under the IRA.

The order increased the annualized base level of net energy costs pursuant to the FAC by approximately $40 million from the base level established in the MoPSC’s December 2021 electric rate order.

The order also changed annualized depreciation, regulatory asset and liability amortization amounts, and the base level of expenses for trackers.

On an annualized basis, these changes reflect approximate increases in “Depreciation and amortization” of $90 million and “Other income, net”, of $100 million, related to non-service pension and postretirement benefit income, on Ameren’s and Ameren Missouri’s consolidated statements of income.

The new rates became effective on July 9, 2023.

In June 2023, Ameren Missouri filed for CCNs with the MoPSC for four solar generation facilities, including the Split Rail Solar Project (300-MW facility, build-transfer agreement), the Cass County Solar Project (150-MW facility, development-transfer agreement), the Vandalia Solar Project (50-MW facility, self-build), and the Bowling Green Solar Project (50-MW facility, self-build).

The stipulation and agreement also requests MoPSC approval of the CCN request for the Cass County Solar Project conditioned upon the facility supporting the Renewable Solutions Program and full subscription of the portion of the program supported by this facility, subject to certain other terms and conditions.

The remaining intervenors did not object to the agreement.

Ameren Missouri expects a decision by the MoPSC in March 2024.

Each project is expected to support Ameren Missouri’s transition to renewable generation and, in addition, the Cass County Solar Project is expected to support Ameren Missouri’s Renewable Solutions Program.

In February and April 2023, the MoPSC issued orders approving requested CCNs for the Huck Finn and Boomtown solar projects, respectively.

In August 2023, the MoPSC issued an order approving a nonunanimous stipulation and agreement to extend Ameren Missouri’s MEEIA 2019 program for an additional year through 2024.

For 2024, the order approved the establishment of a portfolio of customer energy-efficiency programs and performance incentives that will provide Ameren Missouri an opportunity to earn revenues, including $12 million of performance incentive revenues if Ameren Missouri achieves certain program spending goals.

In 2024, Ameren Missouri expects to invest $76 million in energy-efficiency programs.

In January 2024, Ameren Missouri filed a proposed customer energy-efficiency plan with the MoPSC under the MEEIA for 2025 through 2027.

If the plan is approved, Ameren Missouri intends to invest $123 million annually in the proposed customer energy-efficiency programs from 2025 to 2027.

Ameren Missouri also requested additional performance incentives applicable to each plan year totaling up to $14 million over the three-year plan, if Ameren Missouri exceeds 100% of the goals.

Ameren Missouri expects a decision by the MoPSC by October 2024 but cannot predict the ultimate outcome of this regulatory proceeding.

In February 2024, the MoPSC staff filed a response to Ameren Missouri’s petition that stated Ameren Missouri’s decision to accelerate the retirement of the Rush Island Energy Center was prudent and largely supported Ameren Missouri’s securitization request.

Ameren Missouri expects a decision by the MoPSC by the end of June 2024, but cannot predict the ultimate outcome of this regulatory proceeding.

The ICC concluded that the proposed Grid Plan did not meet certain statutory requirements and directed Ameren Illinois to file a revised Grid Plan within three months.

This rate base will remain in effect through 2027, unless subsequently changed by the ICC in the rehearing discussed below or if approval of a revised Grid Plan results in an update of each year’s revenue requirement.

The filing contended that the use of the 2022 year-end rate base for each year of the MYRP, until a revised Grid Plan is approved, is unlawful and not in compliance with the CEJA.

In addition, the filing requested the ICC revise the order to include an allowed ROE of at least 9.82% for each year of the MYRP and include

a base level of investments to maintain grid reliability in each year of the MYRP, among other things.

Additionally, the scope of the rehearing will include a review of certain operations and maintenance expenses in each year of the MYRP.

In February 2024, Ameren Illinois filed its request in the rehearing proceeding, which proposed updated revenue requirements and annual rate base amounts to reflect a base level of investments to maintain grid reliability for 2024 through 2027.

An ICC decision in this rehearing is expected by late June 2024.

Ameren Illinois cannot predict the ultimate outcome of the revised Grid Plan filing, its request to update the associated MYRP revenue requirements for 2024 through 2027, the rehearing proceeding, or the appeal to the Illinois Appellate Court for the Fifth Judicial District.

The following table presents the approved revenue requirements, ROE, capital structure common equity percentage, and annual rate base in the ICC’s December 2023 order, as well as the proposed revenue requirements and annual rate base amounts in Ameren Illinois’ February 2024 rehearing request filing:

| | | | | | | | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

| Year | | | Revenue Requirement (in millions) | | | ROE | | | Capital Structure Common Equity Percentage | | | Annual Rate Base (in billions) | | |

| ICC’s December 2023 MYRP Order: | | | | | | | | | | | | | | |

We manage our interest rate exposure by controlling the amount of debt instruments within our total capitalization [removed: portfolio and] [added: portfolio,] by monitoring the effects of market changes on interest [removed: rates.][added: rates, and by entering into interest rate swaps to hedge a portion of our interest rate risk on cash flows related to forecasted debt issuances.]

The estimated increase in our annual interest expense and decrease in net income if interest rates were to increase by 100 basis points on variable-rate debt outstanding at December 31, [removed: 2023] [added: 2024] is immaterial.

[added: Therefore, Ameren Illinois’] annual ROE for its electric energy-efficiency investments is directly correlated to the yields on such bonds, which are outside of Ameren Illinois’ control.

See Note 7 – Derivative Financial Instruments under Part II, Item 8, of this report for information on the potential loss on counterparty exposure as of December 31, [removed: 2023.][added: 2024.]

At December 31, [removed: 2023,] [added: 2024,] no nonaffiliated customer represented more than 10% of our accounts receivable.

As of December 31, [removed: 2023,] [added: 2024,] Ameren Illinois’ balance of purchased accounts receivable associated with the utility consolidated billing and purchase of receivables services was [removed: $42] [added: $43] million.

Ameren Missouri and Ameren Illinois continue to monitor the impact of economic conditions, including inflationary pressures, on customer [removed: collections and customer account balances.]

Contributions to the plans and future costs could increase materially if we do not achieve pension and postretirement asset portfolio investment returns equal to or in excess of our [removed: 2024] [added: 2025] assumed return on plan assets of 6.75%.

As of December 31, [removed: 2023,] [added: 2024,] this fund was invested in domestic equity securities (68%) and debt securities (31%).

Additionally, Ameren and Ameren Illinois have COLI contracts with net cash surrender values of [removed: $144] [added: $150] million and [removed: $7] [added: $8] million, respectively, as of December 31, [removed: 2023.][added: 2024.]

As of December 31, [removed: 2023,] [added: 2024,] that separate account is comprised of approximately 50% equity securities and 50% debt securities.

Ameren Missouri’s and Ameren Illinois’ electric and natural gas distribution businesses’ exposure to changing market prices for commodities is in large part mitigated [removed: by the fact that] [added: because] there are cost recovery mechanisms in place.

In [removed: 2023,] [added: 2024,] Ameren Illinois procured power on behalf of its customers for [removed: 28%] [added: 25%] of its total kilowatthour sales.

Ameren Illinois has purchased approximately [removed: 15%] [added: 14%] of its [removed: June 2024 to May 2025] [added: summer 2025, 9% of its fall 2025, none of its winter 2025/26 and 2% of its spring 2026] capacity needs bilaterally, however, this percentage beyond May [removed: 2025] [added: 2026] will be dependent on the results of future IPA procurement events.

The following table presents, as of December 31, [removed: 2023,] [added: 2024,] the percentages of the projected required supply of coal and coal transportation for Ameren Missouri’s coal-fired energy centers, nuclear fuel for Ameren Missouri’s Callaway Energy Center, natural gas for Ameren Missouri’s and Ameren Illinois’ retail distribution, and purchased power for Ameren Illinois that are price-hedged over the period [removed: 2024] [added: 2025] through [removed: 2028.][added: 2029.]

| Coal(a) | | | [removed: 98] [added: 93] | | % | | | | [removed: 85] [added: 73] | | % | | | | [removed: 48] [added: 47] | | % |

| Coal transportation(a) | | | [removed: 100] [added: 99] | | | | | | [removed: 100] [added: 99] | | | | | | [removed: 98] [added: 96] | | |

| Nuclear fuel | | | [removed: (b)] [added: 100] | | | | | | 100 | | | | | | 100 | | |

| Natural gas for [removed: distribution(c)] [added: distribution(b)] | | | [removed: 97] [added: 91] | | | | | | [removed: 50] [added: 52] | | | | | | [removed: 27] [added: 25] | | |

| Purchased power for Ameren [removed: Illinois(d)] [added: Illinois(c)] | | | 77 | | | | | | [removed: 37] [added: 36] | | | | | | [removed: 11] [added: 12] | | |

| Natural gas for [removed: distribution(c)] [added: distribution(b)] | | | [removed: 90] [added: 100] | | | | | | [removed: 57] [added: 50] | | | | | | [removed: 31] [added: 26] | | |

| Natural gas for [removed: distribution(c)] [added: distribution(b)] | | | [removed: 98] [added: 100] | | % | | | | 49 | | % | | | | [removed: 26] [added: 27] | | % |

| Purchased [removed: power(d)] [added: power(c)] | | | 77 | | | | | | [removed: 37] [added: 36] | | | | | | [removed: 11] [added: 12] | | |

[removed: (c)Represents] [added: (b)Represents] the percentage of natural gas price-hedged for peak winter season of November through March.

The year [removed: 2024] [added: 2025] represents January [removed: 2024] [added: 2025] through March [removed: 2024.][added: 2025.]

The year [removed: 2025] [added: 2026] represents November [removed: 2024] [added: 2025] through March [removed: 2025.][added: 2026.]

This continues each successive year through March [removed: 2028.][added: 2029.]

[removed: (d)Represents] [added: (c)Represents] the percentage of purchased power price-hedged for fixed-price residential and nonresidential customers with less than 150 kilowatts of demand.

Ameren Missouri has agreements with multiple suppliers to purchase low-sulfur coal through [removed: 2028] [added: 2029] to comply with environmental regulations.

Currently, the Callaway Energy Center has [removed: a single] [added: one] NRC-licensed supplier able to provide fuel assemblies to the Callaway Energy Center.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

collections and customer account balances.

Through the IPA's

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

development and filing of the 2025 Electricity Procurement Plan, the ICC has approved the plan's proposal for multiple IPA procurement events over the following year.

These events will procure portions of Ameren Illinois' energy and capacity forecasted requirements for forward delivery years through May 2028.

| | | | 2025 | | | | | | 2026 | | | | | | 2027 – 2029 | | |

| Coal(a) | | | 93 | | % | | | | 73 | | % | | | | 47 | | % |

| Coal transportation(a) | | | 99 | | | | | | 99 | | | | | | 96 | | |

| Nuclear fuel | | | 100 | | | | | | 100 | | | | | | 100 | | |

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

Therefore, Ameren Illinois’

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

See Note 15 – Supplemental Information under Part II, Item 8, of this report for more information on Ameren’s, Ameren Missouri’s, and Ameren Illinois’ accounts receivable balances that were 30 days or greater past due or that were a part of a deferred payment arrangement as of December 31, 2023.

The IPA has proposed and the ICC has approved multiple procurement events covering portions of years through 2027 for capacity and energy.

| | | | 2024 | | | | | | 2025 | | | | | | 2026 – 2028 | | |

(b)The Callaway Energy Center requires refueling at 18-month intervals.

As there is no refueling and maintenance outage scheduled to occur during 2024, there are also no nuclear fuel deliveries anticipated to occur in 2024.

Ameren Missouri is pursuing a program to qualify an alternate NRC-licensed supplier for contingency purposes.

Ameren Missouri is awaiting approval from the NRC, which is under no deadline to issue the approval.

Ameren Missouri received a planned delivery of enriched uranium from a Russian supplier in the spring of 2023.

The planned delivery concluded the nuclear fuel supply agreement with this Russian supplier with no future deliveries planned with any Russian suppliers.

Ameren Missouri has sufficient inventory and supply contracts with non-Russian suppliers that adequately meet all of the nuclear fuel needs of the Callaway Energy Center through the spring 2028 refueling.

Ameren Missouri's 2023 IRP targets cleaner and more diverse sources of energy generation, including solar generation.

While rights to acquire build-transfer solar facilities and supplies for development-transfer and self-build solar facilities totaling 900 MWs were secured through agreements, supply chain disruptions, including solar panel shortages and increasing material costs as a result of government tariffs and other factors, could affect the costs, as well as the timing, of these projects and other solar generation projects.

See Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report for additional information on the solar facilities.

See Outlook under Part II, Item 7, of this report for additional information on the United States Department of Commerce investigation into the supply of solar panels and the actions taken by the United States Customs and Border Protection Agency to detain certain solar panel shipments from China.

Any future tariffs or actions by the United States Customs and Border Protection Agency could affect the cost and the availability of solar panel components and the timing and amount of Ameren Missouri's estimated capital expenditures associated with solar generation investments.

An illustration of the Ameren Companies’ reporting structures is provided [removed: below:][added: below:]

[removed: (a)] [added: (b)] The Ameren Transmission segment also includes allocated Ameren (parent) interest charges, as well as other subsidiaries engaged in electric transmission project development and investment.

[added: Depending on the] jurisdiction, the effects of regulatory lag are mitigated by various means, including annual revenue requirement reconciliations, the decoupling of revenues from sales volumes to ensure revenues approved in a regulatory rate review are not affected by changes in sales volumes, the recovery of certain capital investments between traditional regulatory rate reviews, the level and timing of expenditures, the use of future test years to establish customer rates, and the use of trackers and riders.

The following table summarizes the key terms of the rate orders in effect for customer billings for each of Ameren’s [removed: rate-regulated] utilities as of January 1, [removed: 2024,] [added: 2025,] except as noted:

| | | | Rate Regulator | | | Effective Rate Order Issued In | | | Rates Effective | | | Allowed ROE | | | Percent of Common Equity | | | Rate Base (in billions) | | | Portion of Ameren’s [removed: 2023] [added: 2024] Operating Revenues(a) | | |

| Electric service(b) | | | MoPSC | | | June 2023 | | | July 2023 | | | (c) | | | (c) | | | (c) | | | [removed: 49%] [added: 50%] | | |

| Electric distribution delivery service(e) | | | ICC | | | December [removed: 2023] [added: 2024] | | | [removed: January 2024] [added: (e)] | | | 8.72% | | | 50.00% | | | [removed: $3.9] [added: (e)] | | | [removed: 29%] [added: 27%] | | |

[removed: (e)In] [added: In] December [removed: 2023,] [added: 2024,] the ICC issued an order [removed: in] [added: approving] Ameren [removed: Illinois'] [added: Illinois’ revised Grid Plan under its] MYRP [removed: proceeding, approving base rates] [added: proceeding] for electric distribution [removed: services] [added: service] for 2024 through 2027.

[removed: The] [added: (e)In] December [removed: 2023] [added: 2024, the] ICC [added: issued an] order [removed: rejected] [added: in] Ameren Illinois’ [removed: Grid Plan, which was addressed as part of the] MYRP proceeding.

The [removed: 10.52%] [added: 10.48%] return, which includes a 50-basis-point incentive adder for participation in an RTO, is based on the FERC’s [removed: May 2020] [added: October 2024] order.

The SERC is one of six regional entities and represents all or portions of 16 central and southeastern states under authority from the NERC for the purpose of [added: implementing and enforcing reliability standards approved by the FERC.]

Ameren Missouri’s Keokuk Energy Center and its dam on the Mississippi River between Hamilton, Illinois, and Keokuk, Iowa, [removed: are operated under authority granted by an Act of Congress in 1905.]

These environmental statutes and regulations are comprehensive and include the storage, handling, and disposal of waste materials and hazardous substances, emergency planning and response requirements, limitations and standards applicable to discharges from our facilities into the air or water that are enforced through permitting requirements, and [removed: wildlife] [added: natural resource] protection laws, including those related to endangered species.

Federal and state authorities [removed: continually revise these] [added: periodically review and modify existing] regulations and adopt new regulations, which may impact our planning process and the ultimate implementation of these or other new or revised regulations.

[removed: Local] [added: Recent] and [added: potential new executive orders issued by the current federal administration as well as local and] state land use requirements can also [removed: potentially] impact our planning activities.

For discussion of environmental matters, including NOx and SO2 emission reduction requirements, regulation of CO2 emissions, wastewater discharge standards, remediation efforts, [added: and] CCR management regulations, and a discussion of litigation against Ameren Missouri with respect to NSR, the Clean Air Act, and Missouri law in connection with projects at Ameren Missouri’s Rush Island Energy Center, see Note 14 – Commitments and Contingencies under Part II, Item 8, of this report.

The AMMO balancing authority area includes the load and most energy centers of Ameren Missouri, and had a peak demand of [removed: 7,836] [added: 7,560] MWs in [removed: 2023.][added: 2024.]

The AMIL balancing authority area includes the load of Ameren Illinois and certain [removed: natural gas-fired] [added: Ameren Missouri] energy centers [removed: of Ameren Missouri,] [added: located in Illinois,] and had a peak demand of [removed: 8,859] [added: 8,479] MWs in [removed: 2023.][added: 2024.]

Ameren Missouri sells [removed: nearly] all of its capacity to the MISO and purchases the capacity it needs to supply its native load sales from the MISO.

Ameren Missouri files a long-term nonbinding [removed: integrated] [added: preferred] resource plan with the MoPSC every three years.

- adding [removed: 2,800] [added: 3,200] MWs of renewable generation by 2030, which includes the 900 MWs of solar generation projects discussed in Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report, and an additional [removed: 1,900] [added: 1,500] MWs by [removed: 2036, representing investment opportunities of $5.3 billion and $4.1 billion, respectively;][added: 2035;]

The addition of [removed: renewable or] [added: renewable,] natural [removed: gas-fired] [added: gas-fired, or nuclear] generation facilities is subject to obtaining necessary project approvals, including FERC approval and the issuance of a CCN by the MoPSC, as applicable.

The next [removed: integrated] [added: preferred] resource plan is [removed: expected] [added: required] to be filed [removed: in September] [added: by October] 2026.

The need for investment in new sources of energy is dependent on several key factors, including continuation of and customer participation in energy-efficiency programs, the amount of distributed generation from customers, load growth, [added: including demand from data centers,] technological advancements, costs of generation alternatives, environmental regulation of coal-fired and natural gas-fired power plants, [added: changes in United States energy policy] and [added: priorities under the current federal administration, and] state renewable energy requirements, which could lead to the retirement of current baseload assets before the end of their current useful lives or alterations in the way those assets operate, which could result in increased capital expenditures and/or increased operations and maintenance expenses.

The difference between the cost of the solar rebates and the amount set in base rates was deferred as a regulatory asset or liability under the RESRAM, and [removed: earn] [added: earns] carrying costs at short-term interest rates.

In [added: 2024,] 2023, [removed: 2022,] and [removed: 2021,] [added: 2022,] Ameren Illinois procured power on behalf of its customers for [removed: 28%,] [added: 25%,] 28%, and [removed: 23%,] [added: 28%,] respectively, of its total kilowatthour sales.

The Grid Plan outlines how Ameren Illinois expects to invest in electric distribution infrastructure in order to support grid modernization, clean energy, energy efficiency, and the state of Illinois’ renewable energy, equity, climate, electrification, and environmental [removed: goals.]

Ameren Missouri owns energy centers that rely on a diverse fuel portfolio, including coal, nuclear, and natural gas, as well as renewable sources of [removed: generation, which include hydroelectric, wind, methane gas, and solar.][added: generation.]

[removed: All] [added: Both] of Ameren Missouri’s coal-fired energy centers were constructed prior to 1978.

As of December 31, [removed: 2023,] [added: 2024,] Ameren Missouri’s coal-fired energy centers represented [removed: 8%] [added: 6%] and [removed: 16%] [added: 11%] of Ameren’s and Ameren Missouri’s rate base, respectively.

Ameren Illinois operates [removed: a] [added: two] solar generation [removed: facility,] [added: facilities,] which [removed: is one of] [added: are] two [added: of three] pilot solar projects Ameren Illinois is allowed to invest in under the CEJA.

The [removed: second] [added: third] solar generation facility is planned [added: to] be placed in service before the end of [removed: 2025.][added: 2026.]

Ameren Missouri burned approximately [removed: 11.5] [added: 10.7] million tons of coal in [removed: 2023.][added: 2024.]

For information regarding the percentages of Ameren Missouri’s projected required supply of coal and coal transportation that are price-hedged through [removed: 2028,] [added: 2029,] see Commodity Price Risk under Part II, Item 7A, of this report.

Delays and disruptions in coal deliveries could cause Ameren Missouri to pursue a strategy that could include reducing off-system sales of power during [removed: low-margin] [added: low-earning] periods, buying higher-cost fuels to generate required electricity, and purchasing power from other sources.

Ameren Missouri and Ameren Illinois satisfied their renewable energy portfolio requirements in [removed: 2023,] [added: 2024,] pending regulatory review by the MoPSC for Ameren Missouri.

Ameren Missouri expects to satisfy the [removed: non-solar] requirement in [removed: 2024] [added: 2025] with its High [removed: Prairie Renewable, Atchison Renewable,] [added: Prairie, Atchison, Huck Finn,] Keokuk, [removed: and] Maryland [removed: Heights] [added: Heights, and other solar] energy centers, [removed: a 102-MW power purchase agreement] [added: along] with [removed: a wind farm operator, which expires in August 2024, and previously] [added: other renewable energy credits] purchased [added: by Ameren Missouri, including solar-generated] renewable energy [removed: credits.][added: credits purchased from customer-installed systems.]

The High Prairie [removed: Renewable] and Atchison [removed: Renewable] energy centers are wind generation facilities.

Based on IPA procurement events that align with the IPA’s plan, Ameren Illinois has contractual commitments to purchase approximately [removed: 1.0] [added: 1.6] million wind renewable energy credits per year and approximately [removed: 3.1] [added: 3.6] million solar renewable energy credits per year.

Pursuant to the CEJA, if funds collected from customers are not used to procure renewable energy credits, they would be refunded to customers pursuant to [removed: a] [added: an annual] reconciliation proceeding, the first of which was [removed: initiated] [added: approved by the ICC] in [removed: August 2023.][added: January 2025, which was the June 2017 through May 2018 reconciliation period, and did not result in refunds to customers.]

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

(a) Ameren Missouri consolidates AMF, which is wholly owned by Ameren Missouri.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

| Electric transmission service(g) | | | FERC | | | (g) | | | January 2025 | | | 10.48% | | | 54.91% | | | $4.4 | | | 6% | | |

| Electric transmission service(g) | | | FERC | | | (g) | | | January 2025 | | | 10.48% | | | 60.08% | | | $1.6 | | | 3% | | |

The order approved an average annual rate base for 2024, 2025, 2026, and 2027 of $4.2 billion, $4.4 billion, $4.6 billion, and $4.8 billion, respectively.

Rate changes consistent with the December 2024 order became effective in late December 2024.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

are operated under authority granted by an Act of Congress in 1905.

The Keokuk Energy Center dam safety program is regulated by the Illinois Department of Natural Resources.

The most recent preferred resource plan was filed in September 2023.

Ameren Missouri expects to file a notice of change in its preferred resource plan with the MoPSC in February 2025 to address new load growth opportunities resulting from entities in various industries, including data center and manufacturing, that are considering either locating or expanding their operations within Ameren Missouri’s service territory.

The 2025 Change to the 2023 PRP is expected to include, among other things, the following:

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

- adding 1,600 MWs of natural gas-fired simple-cycle generation by 2030, which includes the 800-MW Castle Bluff Natural Gas Project discussed in Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report, and an additional 1,200 MWs by 2043;

- adding 2,100 MWs of natural gas-fired combined-cycle generation by 2035 and an additional 1,200 MWs by 2040;

- adding 1,000 MWs of battery storage by 2030 and an additional 800 MWs by 2042;

- adding 1,500 MWs of nuclear generation by 2040;

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

goals.

Renewable

Ameren Missouri operates several renewable energy centers, which includes hydroelectric, wind, methane gas, and solar energy centers.

The Huck Finn, Boomtown, and Cass County energy centers are solar generation facilities.

The Osage and Keokuk energy centers generate electricity using hydroelectric dams located on the Lake of the Ozarks and the Mississippi River, respectively.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

Based on amounts collected from customers and obligations under the program, the June 2018 through May 2019 reconciliation period is not expected to result in refunds to customers, pending review by the ICC.

In November 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement for Ameren Missouri’s MEEIA 2025 plan, which includes a portfolio of customer energy-efficiency and demand response programs, along with the continued use of the MEEIA rider.

Ameren Missouri intends to invest $51 million annually in 2025 and 2026 and $22 million in 2027 for customer energy-efficiency and demand response programs.

In addition, the order approved 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.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

the MEEIA programs are reflected in base rates.

Ameren Illinois’ planned investments in electric energy-efficiency programs is approximately $120 million in 2025 and approximately $125 million annually from 2026 to 2029.

Ameren Illinois is required to file an updated four-year electric energy-efficiency plan with the ICC by March 2025.

In addition to reviewing and determining the Ameren Companies’

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

As such, we seek to develop a strong leadership team with a variety of experiences and perspectives.

| Ameren | | | | | | 8,981 | | | | | | 13 | | | | | | 7% | | | | | |

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

As of December 31, 2024, these labor unions collectively represented 46%, 59%, 55%, and 10% of the employees at Ameren, Ameren Missouri, Ameren Illinois, and Ameren Services, respectively.

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)


Depending on the

| Electric transmission service(g) | | | FERC | | | (g) | | | January 2024 | | | 10.52% | | | 54.90% | | | $3.9 | | | 5% | | |

| Electric transmission service(g) | | | FERC | | | (g) | | | January 2024 | | | 10.52% | | | 60.16% | | | $1.5 | | | 3% | | |

This rate order was based on forecasted recoverable costs and an ICC-determined ROE applied to Ameren Illinois’ 2022 year-end rate base approved by the 2022 electric distribution service revenue requirement reconciliation adjustment order.

The ICC concluded that the proposed Grid Plan did not meet certain statutory requirements and directed Ameren Illinois to file a revised Grid Plan within three months.

Ameren Illinois expects to file a revised Grid Plan with the ICC in March 2024, and also expects to file a request to update the associated MYRP revenue requirements for 2024 through 2027 in the first half of 2024.

The ICC will be under no deadline to act on the revised Grid Plan when filed.

This rate base will remain in effect through 2027, unless the rehearing of the MYRP order or approval of a revised Grid Plan by the ICC results in an update of each year’s revenue requirement.

implementing and enforcing reliability standards approved by the FERC.

In July 2022, the ICC issued an order requiring Ameren Illinois to perform a cost-benefit study of continued participation in the MISO compared to participation in PJM Interconnection LLC, another RTO.

In July 2023, Ameren Illinois filed its cost-benefit study with the ICC.

The study concluded that continued participation in the MISO was prudent and more cost-beneficial than participation in PJM Interconnection LLC.

In January 2024, the ICC staff submitted a report recommending the ICC not take any action with regard to changing Ameren Illinois’ RTO membership.

The ICC is under no obligation to issue an order related to the cost-benefit study.

For additional information regarding the RTO cost-benefit study, see Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report.

In the April 2023 MISO capacity auction, Ameren Missouri’s generation resources exceeded its native load capacity requirements for the June 2023 through May 2024 period.

The most recent integrated resource plan was filed in September 2023 and 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.

The preferred plan includes, among other things, the following:

- adding an 800-MW natural gas-fired simple-cycle energy center by 2027 and an additional 1,200-MW natural gas-fired combined-cycle energy center by 2033, representing investment opportunities of $0.8 billion and $1.7 billion, respectively;

- adding 400 MWs of battery storage by 2030 and an additional 400 MWs by 2035, representing investment opportunities of $0.6 billion and $0.7 billion, respectively;

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

- accelerating the retirement date of the Rush Island coal-fired energy center from 2025 to 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;

In connection with the accelerated retirement of the Rush Island Energy Center, Ameren Missouri is seeking approval from the MoPSC to finance the costs associated with the retirement, including the remaining unrecovered net plant balance associated with the facility, through the issuance of securitized utility tariff bonds pursuant to the Missouri securitization statute.

Ameren Illinois expects to file a revised Grid Plan with the ICC in March 2024 after its initial Grid Plan for the years 2023 to 2027 was rejected by the ICC’s December 2023 order in Ameren Illinois’ MYRP proceeding.

The Keokuk Energy Center generates electricity using a hydroelectric dam located on the Mississippi River.

Ameren Missouri is meeting the solar energy requirement by purchasing solar-generated renewable energy credits from customer-installed systems and by generating energy at its solar facilities.

Based on amounts collected from customers and renewable energy credit purchases under contract, the August 2023 reconciliation proceeding did not result in refunds to customers.

Ameren Illinois has completed its transition to smart meters, which have been installed for nearly all its electric and natural gas customers.

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 approximately $420 million over the life of the plan, including $76 million in 2024.

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.

Additionally, as part of its Smart Energy Plan, Ameren Missouri has invested $336 million in smart meters since 2019.

We seek to foster diversity, equity, and inclusion across our organization.

Our efforts extend to the community through philanthropic contributions and volunteerism, including to support non-profit organizations in leading community-building efforts, providing education and support to our community and company leaders through our diversity leadership summit, providing various training programs, and organizing and promoting opportunities for employee volunteerism.

We also have employee resource groups, which bring together groups of employees who share common interests or backgrounds.

For additional information on material legal and administrative proceedings, see [Note 2 – Rate and Regulatory [removed: Matters](#i9832300923724c57b9a236a12cb814a6_226),] [added: Matters](#i15112ec7ce464e3d9656f6f00b3e12db_229),] [Note 9 – Callaway Energy [removed: Center](#i9832300923724c57b9a236a12cb814a6_253),] [added: Center](#i15112ec7ce464e3d9656f6f00b3e12db_259),] and [Note 14 – Commitments and [removed: Contingencies](#i9832300923724c57b9a236a12cb814a6_271)] [added: Contingencies](#i15112ec7ce464e3d9656f6f00b3e12db_277)] under Part II, Item 8, of this report.

| ☒ | | | Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, [removed: 2023] [added: 2024] | | |

| [removed: ] [added: ] | | | [removed: ] [added: ] | | | [removed: ] [added: ] | | |

As of June [removed: 30, 2023,] [added: 28, 2024,] the aggregate market value of Ameren Corporation’s common stock, $0.01 par value, (based upon the closing price of the common stock on the New York Stock Exchange on June [removed: 30, 2023)] [added: 28, 2024)] held by nonaffiliates was [removed: $21,380,504,079.][added: $18,953,889,643.]

All of the shares of common stock of the other registrants were held by Ameren Corporation as of June [removed: 30, 2023.][added: 28, 2024.]

The number of shares outstanding of each registrant’s classes of common stock as of January 31, [removed: 2024,] [added: 2025,] were as follows:

| Ameren Corporation | | | Common stock, $0.01 par value per share | | | [removed: 266,288,867] [added: 269,906,252] | | |

Portions of the definitive proxy statement of Ameren Corporation and portions of the definitive information statements of Union Electric Company and Ameren Illinois Company for the [removed: 2024] [added: 2025] annual meetings of shareholders are incorporated by reference into Part III of this Form 10-K.

| [GLOSSARY OF TERMS AND [removed: ABBREVIATIONS](#i9832300923724c57b9a236a12cb814a6_10)] [added: ABBREVIATIONS](#i15112ec7ce464e3d9656f6f00b3e12db_10)] | | | | | | | | | [removed: [1](#i9832300923724c57b9a236a12cb814a6_10)] [added: [1](#i15112ec7ce464e3d9656f6f00b3e12db_10)] | | |

| [FORWARD-LOOKING [removed: STATEMENTS](#i9832300923724c57b9a236a12cb814a6_13)] [added: STATEMENTS](#i15112ec7ce464e3d9656f6f00b3e12db_13)] | | | | | | | | | [removed: [4](#i9832300923724c57b9a236a12cb814a6_13)] [added: [5](#i15112ec7ce464e3d9656f6f00b3e12db_13)] | | |

| Item 1. | | | [removed: [Business](#i9832300923724c57b9a236a12cb814a6_19)] [added: [Business](#i15112ec7ce464e3d9656f6f00b3e12db_19)] | | | | | | [removed: [6](#i9832300923724c57b9a236a12cb814a6_19)] [added: [7](#i15112ec7ce464e3d9656f6f00b3e12db_19)] | | |

| | | | [Business [removed: Segments](#i9832300923724c57b9a236a12cb814a6_25)] [added: Segments](#i15112ec7ce464e3d9656f6f00b3e12db_25)] | | | | | | [removed: [7](#i9832300923724c57b9a236a12cb814a6_25)] [added: [7](#i15112ec7ce464e3d9656f6f00b3e12db_25)] | | |

| | | | [Rates and [removed: Regulation](#i9832300923724c57b9a236a12cb814a6_28)] [added: Regulation](#i15112ec7ce464e3d9656f6f00b3e12db_28)] | | | | | | [removed: [7](#i9832300923724c57b9a236a12cb814a6_28)] [added: [8](#i15112ec7ce464e3d9656f6f00b3e12db_28)] | | |

| | | | [Supply of Electric [removed: Power](#i9832300923724c57b9a236a12cb814a6_34)] [added: Power](#i15112ec7ce464e3d9656f6f00b3e12db_34)] | | | | | | [removed: [10](#i9832300923724c57b9a236a12cb814a6_34)] [added: [10](#i15112ec7ce464e3d9656f6f00b3e12db_34)] | | |

| | | | [Power [removed: Generation](#i9832300923724c57b9a236a12cb814a6_37)] [added: Generation](#i15112ec7ce464e3d9656f6f00b3e12db_37)] | | | | | | [removed: [11](#i9832300923724c57b9a236a12cb814a6_37)] [added: [12](#i15112ec7ce464e3d9656f6f00b3e12db_37)] | | |

| | | | [Renewable Energy and Zero Emission [removed: Standards](#i9832300923724c57b9a236a12cb814a6_40)] [added: Standards](#i15112ec7ce464e3d9656f6f00b3e12db_40)] | | | | | | [removed: [12](#i9832300923724c57b9a236a12cb814a6_40)] [added: [12](#i15112ec7ce464e3d9656f6f00b3e12db_40)] | | |

| | | | [Customer Energy-Efficiency [removed: Programs](#i9832300923724c57b9a236a12cb814a6_43)] [added: Programs](#i15112ec7ce464e3d9656f6f00b3e12db_43)] | | | | | | [removed: [13](#i9832300923724c57b9a236a12cb814a6_43)] [added: [13](#i15112ec7ce464e3d9656f6f00b3e12db_43)] | | |

| | | | [Natural Gas Supply for [removed: Distribution](#i9832300923724c57b9a236a12cb814a6_46)] [added: Distribution](#i15112ec7ce464e3d9656f6f00b3e12db_46)] | | | | | | [removed: [14](#i9832300923724c57b9a236a12cb814a6_46)] [added: [14](#i15112ec7ce464e3d9656f6f00b3e12db_46)] | | |

| | | | [Human Capital [removed: Management](#i9832300923724c57b9a236a12cb814a6_49)] [added: Management](#i15112ec7ce464e3d9656f6f00b3e12db_49)] | | | | | | [removed: [14](#i9832300923724c57b9a236a12cb814a6_49)] [added: [14](#i15112ec7ce464e3d9656f6f00b3e12db_49)] | | |

| | | | [Industry [removed: Issues](#i9832300923724c57b9a236a12cb814a6_55)] [added: Issues](#i15112ec7ce464e3d9656f6f00b3e12db_55)] | | | | | | [removed: [16](#i9832300923724c57b9a236a12cb814a6_55)] [added: [16](#i15112ec7ce464e3d9656f6f00b3e12db_55)] | | |

| | | | [Operating [removed: Statistics](#i9832300923724c57b9a236a12cb814a6_58)] [added: Statistics](#i15112ec7ce464e3d9656f6f00b3e12db_58)] | | | | | | [removed: [18](#i9832300923724c57b9a236a12cb814a6_58)] [added: [18](#i15112ec7ce464e3d9656f6f00b3e12db_58)] | | |

| | | | [Available [removed: Information](#i9832300923724c57b9a236a12cb814a6_61)] [added: Information](#i15112ec7ce464e3d9656f6f00b3e12db_61)] | | | | | | [removed: [20](#i9832300923724c57b9a236a12cb814a6_61)] [added: [20](#i15112ec7ce464e3d9656f6f00b3e12db_61)] | | |

| Item 1A. | | | [Risk [removed: Factors](#i9832300923724c57b9a236a12cb814a6_64)] [added: Factors](#i15112ec7ce464e3d9656f6f00b3e12db_64)] | | | | | | [removed: [20](#i9832300923724c57b9a236a12cb814a6_64)] [added: [20](#i15112ec7ce464e3d9656f6f00b3e12db_64)] | | |

| Item 1B. | | | [Unresolved Staff [removed: Comments](#i9832300923724c57b9a236a12cb814a6_67)] [added: Comments](#i15112ec7ce464e3d9656f6f00b3e12db_67)] | | | | | | [removed: [30](#i9832300923724c57b9a236a12cb814a6_67)] [added: [30](#i15112ec7ce464e3d9656f6f00b3e12db_67)] | | |

| Item 1C. | | | [removed: [Cybersecurity](#i9832300923724c57b9a236a12cb814a6_2738)] [added: [Cybersecurity](#i15112ec7ce464e3d9656f6f00b3e12db_70)] | | | | | | [removed: [30](#i9832300923724c57b9a236a12cb814a6_2738)] [added: [30](#i15112ec7ce464e3d9656f6f00b3e12db_70)] | | |

| Item 2. | | | [removed: [Properties](#i9832300923724c57b9a236a12cb814a6_70)] [added: [Properties](#i15112ec7ce464e3d9656f6f00b3e12db_73)] | | | | | | [removed: [31](#i9832300923724c57b9a236a12cb814a6_70)] [added: [31](#i15112ec7ce464e3d9656f6f00b3e12db_73)] | | |

| Item 3. | | | [Legal [removed: Proceedings](#i9832300923724c57b9a236a12cb814a6_73)] [added: Proceedings](#i15112ec7ce464e3d9656f6f00b3e12db_76)] | | | | | | [removed: [33](#i9832300923724c57b9a236a12cb814a6_73)] [added: [33](#i15112ec7ce464e3d9656f6f00b3e12db_76)] | | |

| Item 4. | | | [Mine Safety [removed: Disclosures](#i9832300923724c57b9a236a12cb814a6_76)] [added: Disclosures](#i15112ec7ce464e3d9656f6f00b3e12db_79)] | | | | | | [removed: [33](#i9832300923724c57b9a236a12cb814a6_76)] [added: [33](#i15112ec7ce464e3d9656f6f00b3e12db_79)] | | |

| Item 5. | | | [Market for Registrants’ Common Equity, Related Stockholder [removed: Matters, and] [added: Matters](#i15112ec7ce464e3d9656f6f00b3e12db_88) [and] Issuer [removed: Purchase](#i9832300923724c57b9a236a12cb814a6_85)[s](#i9832300923724c57b9a236a12cb814a6_85) [of] [added: Purchases of] Equity [removed: Securities](#i9832300923724c57b9a236a12cb814a6_85)] [added: Securities](#i15112ec7ce464e3d9656f6f00b3e12db_88)] | | | | | | [removed: [36](#i9832300923724c57b9a236a12cb814a6_85)] [added: [34](#i15112ec7ce464e3d9656f6f00b3e12db_88)] | | |

| Item 6. | | | [removed: [(Reserved)](#i9832300923724c57b9a236a12cb814a6_88)] [added: [(Reserved)](#i15112ec7ce464e3d9656f6f00b3e12db_91)] | | | | | | [removed: [37](#i9832300923724c57b9a236a12cb814a6_88)] [added: [35](#i15112ec7ce464e3d9656f6f00b3e12db_91)] | | |

| Item 7. | | | [Management’s Discussion and Analysis of Financial Condition and Results of [removed: Operations](#i9832300923724c57b9a236a12cb814a6_94)] [added: Operations](#i15112ec7ce464e3d9656f6f00b3e12db_97)] | | | | | | [removed: [37](#i9832300923724c57b9a236a12cb814a6_94)] [added: [35](#i15112ec7ce464e3d9656f6f00b3e12db_97)] | | |

| | | | [Liquidity and Capital [removed: Resources](#i9832300923724c57b9a236a12cb814a6_121)] [added: Resources](#i15112ec7ce464e3d9656f6f00b3e12db_124)] | | | | | | [removed: [57](#i9832300923724c57b9a236a12cb814a6_121)] [added: [57](#i15112ec7ce464e3d9656f6f00b3e12db_124)] | | |

| Item 7A. | | | [Quantitative and Qualitative Disclosures About Market [removed: Risk](#i9832300923724c57b9a236a12cb814a6_166)] [added: Risk](#i15112ec7ce464e3d9656f6f00b3e12db_169)] | | | | | | [removed: [78](#i9832300923724c57b9a236a12cb814a6_166)] [added: [77](#i15112ec7ce464e3d9656f6f00b3e12db_169)] | | |

| Item 8. | | | [Financial Statements and Supplementary [removed: Data](#i9832300923724c57b9a236a12cb814a6_172)] [added: Data](#i15112ec7ce464e3d9656f6f00b3e12db_175)] | | | | | | [removed: [82](#i9832300923724c57b9a236a12cb814a6_172)] [added: [80](#i15112ec7ce464e3d9656f6f00b3e12db_175)] | | |

| | | | [Note 1. Summary of Significant Accounting [removed: Policies](#i9832300923724c57b9a236a12cb814a6_223)] [added: Policies](#i15112ec7ce464e3d9656f6f00b3e12db_226)] | | | | | | [removed: [100](#i9832300923724c57b9a236a12cb814a6_223)] [added: [98](#i15112ec7ce464e3d9656f6f00b3e12db_226)] | | |

| | | | [Note 2. Rate and Regulatory [removed: Matters](#i9832300923724c57b9a236a12cb814a6_226)] [added: Matters](#i15112ec7ce464e3d9656f6f00b3e12db_229)] | | | | | | [removed: [105](#i9832300923724c57b9a236a12cb814a6_226)] [added: [103](#i15112ec7ce464e3d9656f6f00b3e12db_229)] | | |

| | | | [Note 3. Property, Plant, and Equipment, [removed: Net](#i9832300923724c57b9a236a12cb814a6_229)] [added: Net](#i15112ec7ce464e3d9656f6f00b3e12db_235)] | | | | | | [removed: [116](#i9832300923724c57b9a236a12cb814a6_229)] [added: [115](#i15112ec7ce464e3d9656f6f00b3e12db_235)] | | |

| | | | [Note 4. Short-term Debt and [removed: Liquidity](#i9832300923724c57b9a236a12cb814a6_232)] [added: Liquidity](#i15112ec7ce464e3d9656f6f00b3e12db_238)] | | | | | | [removed: [117](#i9832300923724c57b9a236a12cb814a6_232)] [added: [116](#i15112ec7ce464e3d9656f6f00b3e12db_238)] | | |

| | | | [Note 5. Long-term Debt and Equity [removed: Financings](#i9832300923724c57b9a236a12cb814a6_235)] [added: Financings](#i15112ec7ce464e3d9656f6f00b3e12db_241)] | | | | | | [removed: [120](#i9832300923724c57b9a236a12cb814a6_235)] [added: [119](#i15112ec7ce464e3d9656f6f00b3e12db_241)] | | |

| | | | [Note 6. Other Income, [removed: Net](#i9832300923724c57b9a236a12cb814a6_241)] [added: Net](#i15112ec7ce464e3d9656f6f00b3e12db_247)] | | | | | | [removed: [127](#i9832300923724c57b9a236a12cb814a6_241)] [added: [126](#i15112ec7ce464e3d9656f6f00b3e12db_247)] | | |

| | | | [Note 7. Derivative Financial [removed: Instruments](#i9832300923724c57b9a236a12cb814a6_244)] [added: Instruments](#i15112ec7ce464e3d9656f6f00b3e12db_250)] | | | | | | [removed: [127](#i9832300923724c57b9a236a12cb814a6_244)] [added: [126](#i15112ec7ce464e3d9656f6f00b3e12db_250)] | | |

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

| [PART I](#i15112ec7ce464e3d9656f6f00b3e12db_16) | | | | | | | | | | | |

| | | | [General](#i15112ec7ce464e3d9656f6f00b3e12db_22) | | | | | | [7](#i15112ec7ce464e3d9656f6f00b3e12db_22) | | |

| | | | [Transmission](#i15112ec7ce464e3d9656f6f00b3e12db_31) | | | | | | [10](#i15112ec7ce464e3d9656f6f00b3e12db_31) | | |

| [PART II](#i15112ec7ce464e3d9656f6f00b3e12db_85) | | | | | | | | | | | |

| | | | [Overview](#i15112ec7ce464e3d9656f6f00b3e12db_103) | | | | | | [36](#i15112ec7ce464e3d9656f6f00b3e12db_103) | | |

| | | | [Results of Operations](#i15112ec7ce464e3d9656f6f00b3e12db_109) | | | | | | [41](#i15112ec7ce464e3d9656f6f00b3e12db_109) | | |

| | | | [Outlook](#i15112ec7ce464e3d9656f6f00b3e12db_157) | | | | | | [67](#i15112ec7ce464e3d9656f6f00b3e12db_157) | | |

| | | | [Regulatory Matters](#i15112ec7ce464e3d9656f6f00b3e12db_160) | | | | | | [73](#i15112ec7ce464e3d9656f6f00b3e12db_160) | | |

| | | | [Accounting Matters](#i15112ec7ce464e3d9656f6f00b3e12db_163) | | | | | | [73](#i15112ec7ce464e3d9656f6f00b3e12db_163) | | |

| | | | [Ameren Corporation](#i15112ec7ce464e3d9656f6f00b3e12db_187) | | | | | | [86](#i15112ec7ce464e3d9656f6f00b3e12db_187) | | |

| | | | [Union Electric](#i15112ec7ce464e3d9656f6f00b3e12db_199) | | | | | | [90](#i15112ec7ce464e3d9656f6f00b3e12db_199) | | |

| | | | [Ameren Illinois](#i15112ec7ce464e3d9656f6f00b3e12db_211) | | | | | | [94](#i15112ec7ce464e3d9656f6f00b3e12db_211) | | |

| [PART III](#i15112ec7ce464e3d9656f6f00b3e12db_307) | | | | | | | | | | | |

| [PART IV](#i15112ec7ce464e3d9656f6f00b3e12db_325) | | | | | | | | | | | |

| | | | [EXHIBIT INDEX](#i15112ec7ce464e3d9656f6f00b3e12db_349) | | | | | | [171](#i15112ec7ce464e3d9656f6f00b3e12db_349) | | |

| [SIGNATURES](#i15112ec7ce464e3d9656f6f00b3e12db_352) | | | | | | | | | [179](#i15112ec7ce464e3d9656f6f00b3e12db_352) | | |

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

2025 Change to the 2023 PRP – A change to Ameren’s 2023 PRP expected to be filed with the MoPSC in February 2025 reflecting certain modifications to Ameren Missouri’s preferred plan for meeting customers’ projected long-term energy needs.

Ameren Missouri – Union Electric Company and its subsidiary, AMF, on a consolidated basis.

AMF – Ameren Missouri Securitization Funding I, LLC, a special purpose entity wholly owned by Ameren Missouri, was formed in 2024, for the purpose of issuing and servicing securitized utility tariff bonds related to Rush Island Energy Center retirement costs.

CODMs – Chief operating decision makers.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

MEEIA 2025 – Ameren Missouri’s portfolio of customer energy-efficiency and demand response programs, recovery of lost electric revenues, and performance incentives for January 2025 through February 2028, pursuant to Missouri law, as approved by the MoPSC in November 2024.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

RBA – Revenue balancing adjustment rider, a rate-adjustment mechanism for Ameren Illinois’ electric distribution business that decouples electric distribution revenues approved by the ICC from actual sales volumes and/or wholesale and miscellaneous revenue and allows Ameren Illinois to adjust electric distribution service rates charged to customers without an MYRP or a traditional regulatory rate review, subject to ICC prudence reviews.

The rider ensures that Ameren Illinois’ electric distribution revenues are not affected by changes in sales volumes, including those resulting from deviations from normal weather conditions, or wholesale and miscellaneous revenues.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

energy storage, and private generation sources, which generate electricity at the site of consumption and are becoming increasingly cost-competitive;

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

- the inability of our counterparties to perform their obligations, disruptions in the capital and credit markets, prolonged government shutdowns or defunding, acts of sabotage or terrorism, including cyberattacks and physical attacks, and other impacts on business, economic, and geopolitical conditions, including inflation, tariffs, trade wars, or recession.

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

The following security is registered pursuant to Section 12(b) of the Securities Exchange Act of 1934 and is listed on the New York Stock Exchange:

| [PART I](#i9832300923724c57b9a236a12cb814a6_16) | | | | | | | | | | | |

| | | | [General](#i9832300923724c57b9a236a12cb814a6_22) | | | | | | [6](#i9832300923724c57b9a236a12cb814a6_22) | | |

| | | | [Transmission](#i9832300923724c57b9a236a12cb814a6_31) | | | | | | [9](#i9832300923724c57b9a236a12cb814a6_31) | | |

| [Information about Our Executive Officers](#i9832300923724c57b9a236a12cb814a6_79) | | | | | | | | | [34](#i9832300923724c57b9a236a12cb814a6_79) | | |

| [PART II](#i9832300923724c57b9a236a12cb814a6_82) | | | | | | | | | | | |

| | | | [Overview](#i9832300923724c57b9a236a12cb814a6_100) | | | | | | [38](#i9832300923724c57b9a236a12cb814a6_100) | | |

| | | | [Results of Operations](#i9832300923724c57b9a236a12cb814a6_106) | | | | | | [42](#i9832300923724c57b9a236a12cb814a6_106) | | |

| | | | [Outlook](#i9832300923724c57b9a236a12cb814a6_154) | | | | | | [67](#i9832300923724c57b9a236a12cb814a6_154) | | |

| | | | [Regulatory Matters](#i9832300923724c57b9a236a12cb814a6_157) | | | | | | [74](#i9832300923724c57b9a236a12cb814a6_157) | | |

| | | | [Accounting Matters](#i9832300923724c57b9a236a12cb814a6_160) | | | | | | [74](#i9832300923724c57b9a236a12cb814a6_160) | | |

| | | | [Ameren Corporation](#i9832300923724c57b9a236a12cb814a6_184) | | | | | | [88](#i9832300923724c57b9a236a12cb814a6_184) | | |

| | | | [Union Electric](#i9832300923724c57b9a236a12cb814a6_196) | | | | | | [92](#i9832300923724c57b9a236a12cb814a6_196) | | |

| | | | [Ameren Illinois](#i9832300923724c57b9a236a12cb814a6_208) | | | | | | [96](#i9832300923724c57b9a236a12cb814a6_208) | | |

| [PART III](#i9832300923724c57b9a236a12cb814a6_298) | | | | | | | | | | | |

| [PART IV](#i9832300923724c57b9a236a12cb814a6_316) | | | | | | | | | | | |

| [EXHIBIT INDEX](#i9832300923724c57b9a236a12cb814a6_340) | | | | | | | | | [170](#i9832300923724c57b9a236a12cb814a6_340) | | |

| [SIGNATURES](#i9832300923724c57b9a236a12cb814a6_343) | | | | | | | | | [177](#i9832300923724c57b9a236a12cb814a6_343) | | |

Formerly referred to as the Illinois Energy Transition Legislation or IETL in previous filings.

Electric margins – Electric revenues less fuel and purchased power costs.

ESG – Environmental, social, and governance.

MW-day – Megawatt-day, a measure of electric generation equivalent to one MW of power generated over one day.

Natural gas margins – Natural gas revenues less natural gas purchased for resale.

Prior to this change, 95% of these sales were included in the FAC and 5% were included in the RESRAM.

The program is designed to continuously assess risk and evaluate the likelihood and probability of impact [removed: in order] to determine the appropriate risk tolerance and risk management strategies that inform our cybersecurity policies, investments, practices, controls, and countermeasures.

The program is a comprehensive, consistently applied management framework that is designed to ensure all forms of material risk and opportunity are identified, [removed: reported] [added: reported,] and managed in an effective manner overseen by the risk management steering [added: committee.]

The risk management steering committee, which is composed of [added: executive management and] senior-level Ameren officers, with Ameren board of directors’ oversight, oversees [added: and governs] Ameren's enterprise risk management processes, which include the identification, assessment, mitigation, and monitoring of risks including strategic, operational, and cybersecurity risks.

Ameren's board of directors maintains a standing committee, the Cybersecurity and Digital Technology Committee, [removed: that] [added: which] is [removed: dedicated to] [added: focused on] the oversight of Ameren's cybersecurity and digital technology risks.

The committee has primary responsibility for oversight of cybersecurity and digital technology risk management, including the programs, policies, [removed: practices,] [added: procedures, processes,] controls and safeguards for digital technology, information security, prevention and detection of cybersecurity incidents [removed: and information] or data breaches, and cybersecurity and digital technology matters as they relate to crisis preparedness, incident response plans, and disaster recovery and business continuity capabilities.

The committee receives regular updates from the Chief [removed: Customer and Technology Officer, the Chief] Information [added: Security] Officer, the Chief Information [removed: Security] Officer, [added: executive management,] and other members of senior management [removed: regarding] [added: who collectively maintain the responsibility for both the execution and ongoing management of] Ameren’s cybersecurity program and [removed: key] [added: respective] initiatives.

Ameren's cybersecurity program and team are led by the Chief Information Security Officer, who possesses [added: over] 25 years of critical infrastructure experience both managing and protecting information systems in concert with extensive cybersecurity operations and leadership roles.

In addition, [removed: the] [added: Ameren’s] board of directors participate in periodic cybersecurity drills to prepare for potential crisis scenarios.

To manage against existing [removed: conduct] and [removed: new] [added: emerging] cybersecurity threats, we maintain enterprise-wide cybersecurity, crisis management, and information security policies and regular training and tests that reinforce the acceptable use of Ameren's information assets, protection of customer and employee data, and the role each employee plays in protecting Ameren against cybersecurity threats.

Incident response plans and procedures are [added: continuously] tested through recurring companywide cybersecurity exercises to promote readiness across the organization.

The [added: plans and] procedures are also designed to escalate incidents to appropriate members of management to guide the [added: prevention,] detection, response, [added: recovery,] and [removed: recovery] [added: remediation] from a material cybersecurity incident.

To address cybersecurity threats, [removed: cybersecurity intelligence, as well as responding to cyber-related incidents,] we work closely with law enforcement, cybersecurity consulting firms, and industry associations to enhance information sharing and guard against cybersecurity attacks.

[removed: We measure our cybersecurity] [added: Our program] effectiveness [added: is measured] through formal cybersecurity scorecards and metrics reported to senior-level Ameren officers, the risk management steering [removed: committee, and the Cybersecurity and Digital Technology Committee.]

These metrics include but are not limited to measures [removed: around] [added: on] the effectiveness of our cybersecurity [removed: controls,] [added: controls across core National Institute of Standards and Technology Cybersecurity framework functions (Govern, Identify, Protect, Detect, Respond, and Recover),] our ability to manage [added: first- and third-party] cybersecurity events and incidents, cybersecurity incident response exercises, [removed: and] results of our recurring internal assessments, [added: vulnerability assessments, penetration tests,] external assessments, and audits that Ameren regularly undergoes.

These engagements provide insights into control [removed: performance,] [added: design and implementation,] prioritized recommendations for enhancements to our cybersecurity strategy, and an overview of the cybersecurity threat landscape that collectively inform our investments and technical controls to protect Ameren's most critical assets.

The results of these engagements are reviewed with senior-level Ameren [removed: officers] [added: officers, the risk management steering committee,] and the Cybersecurity and Digital Technology Committee.

Ameren [removed: also deploys] [added: employs] a third-party cybersecurity risk management program, which extends the governance elements [removed: described above] [added: of Ameren’s cybersecurity program, in addition] to [added: other diligence measures, to] our [added: critical] third-party providers and suppliers.

These cybersecurity plans and procedures are positioned to promote the expedient identification, escalation, handling and reporting of a potentially material cybersecurity event or incident.

We leverage common and widely accepted external cybersecurity risk management frameworks, such as the National Institute of Standards and Technology Cybersecurity framework, to assess, guide, and enhance our cybersecurity posture.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

committee, and the Cybersecurity and Digital Technology Committee.

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

committee.

Ameren’s board of directors is also regularly updated on its cybersecurity program.

The following table shows the anticipated capability of our energy centers at the time of the expected [removed: 2024] [added: 2025] peak summer electrical demand for all energy centers owned as of December 31, [removed: 2023:][added: 2024:]

| | | | [removed: Sioux(d)] [added: Sioux(c)] | | | St. Charles County, Missouri | | | 972,000 | | |

| Total coal | | | | | | | | | [removed: 4,522,000] [added: 3,344,000] | | |

| Nuclear | | | [removed: Callaway(e)] [added: Callaway(d)] | | | Callaway County, Missouri | | | 1,194,000 | | |

| Hydroelectric | | | [removed: Osage(e)] [added: Osage(d)] | | | Lakeside, Missouri | | | 235,000 | | |

| Pumped-storage | | | Taum [removed: Sauk(e)] [added: Sauk(d)] | | | Reynolds County, Missouri | | | 440,000 | | |

| Wind | | | High Prairie [removed: Renewable] | | | Adair and Schuyler Counties, Missouri | | | 400,000 | | |

| | | | Atchison [removed: Renewable] | | | Atchison County, Missouri | | | 298,800 | | |

| | | | [removed: Venice(f)] [added: Venice(g)] | | | Venice, Illinois | | | 487,000 | | |

| | | | Goose [removed: Creek(f)] [added: Creek(g)] | | | Piatt County, Illinois | | | 438,000 | | |

| | | | [removed: Pinckneyville(f)] [added: Pinckneyville(g)] | | | Pinckneyville, Illinois | | | 316,000 | | |

| | | | Raccoon [removed: Creek(f)] [added: Creek(g)] | | | Clay County, Illinois | | | 304,000 | | |

| | | | [removed: Kinmundy(f)] [added: Kinmundy(g)] | | | Kinmundy, Illinois | | | 210,000 | | |

| Oil (CTs) | | | [removed: Fairgrounds(g)] [added: Fairgrounds(h)] | | | Jefferson City, Missouri | | | 55,000 | | |

| | | | [removed: Mexico(g)] [added: Mexico(h)] | | | Mexico, Missouri | | | 54,000 | | |

| | | | [removed: Moberly(g)] [added: Moberly(h)] | | | Moberly, Missouri | | | 54,000 | | |

| | | | [removed: Moreau(g)] [added: Moreau(h)] | | | Jefferson City, Missouri | | | 54,000 | | |

| | | | Other [removed: Solar(h)] [added: Solar(f)] | | | Various | | | [removed: 1,400] [added: 15,300] | | |

| Total solar | | | | | | | | | [removed: 15,300] [added: 515,300] | | |

| Total Ameren Missouri | | | | | | | | | [removed: 10,014,100] [added: 9,336,100] | | |

| Solar | | | East St. Louis [added: I] | | | East St. Louis, Illinois | | | 2,500 | | |

[removed: (d)As noted in the 2023 IRP, Ameren] [added: (c)Ameren] Missouri plans to extend the retirement date of the Sioux Energy Center from 2030 to 2032, which is subject to the approval of a change in depreciable lives of the energy center’s assets by the [removed: MoPSC.][added: MoPSC in Ameren Missouri’s 2024 electric service regulatory rate review.]

[removed: (e)The] [added: (d)The] operating licenses for the Callaway, Osage, and Taum Sauk energy centers expire in 2044, 2047, and 2044, respectively.

[removed: (f)The] [added: (g)The] Venice Energy Center is scheduled to retire by the end of 2029 and the Goose Creek, Pinckneyville, Raccoon Creek, and Kinmundy energy centers are scheduled to retire by the end of [removed: 2039 as noted in the 2023 IRP.][added: 2039.]

[removed: (g)The] [added: (h)The] Fairgrounds, Mexico, Moberly, and Moreau energy centers are scheduled to [removed: be retired] [added: retire] by the end of [removed: 2029 as noted in the 2023 IRP.][added: 2029.]

[removed: (h)Includes five] [added: (f)Includes 10] solar energy centers that each have a nameplate capacity of [removed: 500] [added: 6,000] kilowatts or less.

The following table presents in-service electric and natural gas utility-related properties for Ameren Missouri and Ameren Illinois as of December 31, [removed: 2023:][added: 2024:]

| Circuit miles of electric transmission lines(a) | | | [removed: 3,140] [added: 3,114] | | | | | | [removed: 4,761] [added: 4,786] | | |

| Circuit miles of electric distribution lines | | | [removed: 33,927] [added: 34,319] | | | | | | [removed: 45,984] [added: 46,299] | | |

| Percentage of circuit miles of electric distribution lines underground | | | [removed: 24] [added: 25] | | % | | | | 16 | | % |

| Miles of natural gas transmission and distribution mains | | | [removed: 3,532] [added: 3,558] | | | | | | [removed: 18,713] [added: 18,750] | | |

The exceptions as of December 31, [removed: 2023] [added: 2024] are as follows:

That property includes a portion of Ameren Missouri’s Osage Energy Center reservoir; certain facilities at Ameren Missouri’s Sioux Energy Center; most of Ameren Missouri’s High Prairie [removed: Renewable] and Atchison [removed: Renewable] energy centers; Ameren Missouri’s [removed: BJC, Cape Girardeau, Lambert,] [added: Boomtown, Cass County, Huck Finn,] and Maryland Heights energy centers; certain substations; and most transmission and distribution lines and natural gas mains.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

| Solar | | | Huck Finn(e) | | | Audrain and Ralls Counties, Missouri | | | 200,000 | | |

| | | | Boomtown | | | White County, Illinois | | | 150,000 | | |

| | | | Cass County | | | Cass County, Illinois | | | 150,000 | | |

| | | | East St. Louis II | | | East St. Louis, Illinois | | | 1,900 | | |

| Total Ameren | | | | | | | | | 9,340,500 | | |

See Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report for additional information on Ameren Missouri’s request to extend the retirement date of the Sioux Energy Center.

(e)There were economic development arrangements applicable to this solar energy center, as discussed below.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

Ameren Missouri operates the Huck Finn Energy Center located in Audrain and Ralls Counties, Missouri.

Ameren Missouri has rights and obligations as the operator of the energy center under long-term agreements with Audrain and Ralls Counties.

Under the terms of these agreements, Ameren Missouri is responsible for all operation and maintenance for the energy center.

The agreements are scheduled to expire in December 2059, at which time the property, plant, and equipment will become subject to the lien of the Ameren Missouri mortgage bond indenture.

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

| | | | Rush Island(c) | | | Jefferson County, Missouri | | | 1,178,000 | | |

| Solar | | | Montgomery County | | | Montgomery County, Missouri | | | 5,700 | | |

| | | | O’Fallon | | | O’Fallon, Missouri | | | 4,500 | | |

| | | | BJC | | | St. Louis, Missouri | | | 1,600 | | |

| | | | Cape Girardeau | | | Cape Girardeau, Missouri | | | 1,200 | | |

| | | | Lambert | | | St. Louis County, Missouri | | | 900 | | |

| Total Ameren | | | | | | | | | 10,016,600 | | |

(c)The Rush Island Energy Center is scheduled to retire by October 15, 2024 per the remedy order of the United States District Court for the Eastern District of Missouri.

For additional information, see NSR and Clean Air Act Litigation in Note 14 – Commitments and Contingencies under Part II, Item 8, of this report.

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

INFORMATION ABOUT OUR EXECUTIVE OFFICERS:

The executive officers of the Ameren Companies, including major subsidiaries, are listed below, along with their ages as of December 31, 2023, all their positions and offices held with the Ameren Companies as of February 29, 2024, and their tenures as officers, and their titles for at least the last five years.

AMEREN CORPORATION:

| | | | | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

| Name | | | Age | | | Positions | | | Period | | |

| Martin J. Lyons, Jr. | | | 57 | | | Chairman, President, and Chief Executive Officer; Ameren | | | January 2022(a) – Present | | |

| | | | | | | Chairman and President; Ameren Missouri | | | December 2019 – January 2022 | | |

| | | | | | | Chairman and President; Ameren Services | | | March 2016 – December 2019 | | |

| | | | | | | Executive Vice President and Chief Financial Officer; Ameren | | | January 2013 – December 2019 | | |

| Michael L. Moehn | | | 54 | | | Senior Executive Vice President and Chief Financial Officer; Ameren | | | March 2023 – Present | | |

| | | | | | | Chairman and President; Ameren Services | | | December 2019 – Present | | |

| | | | | | | Executive Vice President and Chief Financial Officer; Ameren | | | December 2019 – February 2023 | | |

| | | | | | | Chairman and President; Ameren Missouri | | | April 2014 – December 2019 | | |

| Chonda J. Nwamu | | | 52 | | | Executive Vice President, General Counsel, and Secretary; Ameren | | | March 2023 – Present | | |

| | | | | | | Senior Vice President, General Counsel, and Secretary; Ameren | | | August 2019 – February 2023 | | |

| | | | | | | Senior Vice President and Deputy General Counsel; Ameren Services | | | January 2019 – August 2019 | | |

| Theresa A. Shaw | | | 51 | | | Senior Vice President, Finance, and Chief Accounting Officer; Ameren | | | August 2021 – Present | | |

| | | | | | | Senior Vice President, Regulatory Affairs and Financial Services; Ameren Illinois | | | September 2019 – August 2021 | | |

| | | | | | | Vice President, Regulatory Affairs and Financial Services; Ameren Illinois | | | July 2018 – August 2019 | | |

(a)Elected President and Chief Executive Officer of Ameren in January 2022, and Chairman of Ameren in November 2023.

SUBSIDIARIES:

| Bhavani Amirthalingam | | | 48 | | | Executive Vice President and Chief Customer and Technology Officer; Ameren Services | | | March 2023 – Present | | |

| | | | | | | Senior Vice President and Chief Digital Information Officer; Ameren Services | | | March 2018 – February 2023 | | |

| Mark C. Birk | | | 59 | | | Chairman and President; Ameren Missouri | | | January 2022 – Present | | |

| | | | | | | Senior Vice President, Customer and Power Operations; Ameren Missouri | | | October 2017 – January 2022 | | |

| Fadi M. Diya | | | 61 | | | Senior Vice President and Chief Nuclear Officer; Ameren Missouri | | | January 2014 – Present | | |

| Mark C. Lindgren | | | 56 | | | Executive Vice President, Corporate Communications, and Chief Human Resources Officer; Ameren Services | | | March 2023 – Present | | |

| | | | | | | Senior Vice President, Corporate Communications, and Chief Human Resources Officer; Ameren Services | | | September 2015 – February 2023 | | |

| Gwendolyn G. Mizell | | | 62 | | | Senior Vice President and Chief Sustainability, Diversity, & Philanthropy Officer; Ameren Services | | | March 2023 – Present | | |

| | | | | | | Vice President, Chief Sustainability, Diversity, & Philanthropy Officer; Ameren Services | | | March 2022 – February 2023 | | |

| | | | | | | Vice President, Innovation, and Chief Sustainability Officer; Ameren Services | | | January 2021 – March 2022 | | |

| | | | | | | Vice President, Sustainability and Electrification; Ameren Services | | | June 2019 – January 2021 | | |

| | | | | | | Senior Director, Corporate Social Responsibility; Ameren Services | | | March 2018 – June 2019 | | |

| Shawn E. Schukar | | | 62 | | | Chairman and President; ATXI | | | May 2017 – Present | | |

| Leonard P. Singh | | | 54 | | | Chairman and President; Ameren Illinois | | | August 2022(a) – Present | | |

(a)Leonard P.

Singh served as Senior Vice President of Consolidated Edison Company of New York from December 2020 to June 2022 and as Vice President, Manhattan Electric Operations of Consolidated Edison Company of New York from June 2015 to December 2020.

Officers are generally elected or appointed annually by the respective board of directors of each company, following the election of board members at the annual meetings of shareholders.

Ameren common shareholders of record totaled [removed: 35,157] [added: 33,414] on January 31, [removed: 2024.][added: 2025.]

Ameren Corporation, Ameren Missouri, and Ameren Illinois did not purchase any equity securities reportable under Item 703 of Regulation S-K during the period from October 1, [removed: 2023,] [added: 2024,] to December 31, [removed: 2023.][added: 2024.]

The following graph shows Ameren’s cumulative TSR during the five years ended December 31, [removed: 2023.][added: 2024.]

The comparison assumes that $100 was invested on December 31, [removed: 2018,] [added: 2019,] in Ameren common stock and in each of the indices shown and that all of the dividends were reinvested.

[removed: ][added: ]

| December 31, | | | [removed: 2018] [added: 2019] | | | | | | [removed: 2019] [added: 2020] | | | | | | [removed: 2020] [added: 2021] | | | | | | [removed: 2021] [added: 2022] | | | | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2023] [added: 2024] | | |

[Table](#i15112ec7ce464e3d9656f6f00b3e12db_7) [of Contents](#i15112ec7ce464e3d9656f6f00b3e12db_7)

| Ameren (AEE) | | | $ | 100.00 | | | | | $ | 104.27 | | | | | $ | 122.09 | | | | | $ | 125.19 | | | | | $ | 105.07 | | | | | $ | 133.96 | |

| S&P 500 Index | | | 100.00 | | | | | | 118.39 | | | | | | 152.34 | | | | | | 124.73 | | | | | | 157.48 | | | | | | 196.85 | | |

| S&P 500 Utility Index | | | 100.00 | | | | | | 100.52 | | | | | | 118.29 | | | | | | 120.14 | | | | | | 111.63 | | | | | | 137.79 | | |

| Philadelphia Utility Index | | | 100.00 | | | | | | 102.72 | | | | | | 121.46 | | | | | | 122.25 | | | | | | 111.05 | | | | | | 134.24 | | |

[Table](#i9832300923724c57b9a236a12cb814a6_7) [of Conten](#i9832300923724c57b9a236a12cb814a6_7)[t](#i9832300923724c57b9a236a12cb814a6_7)[s](#i9832300923724c57b9a236a12cb814a6_7)

| Ameren (AEE) | | | $ | 100.00 | | | | | $ | 120.82 | | | | | $ | 125.98 | | | | | $ | 147.51 | | | | | $ | 151.26 | | | | | $ | 126.94 | |

| S&P 500 Index | | | 100.00 | | | | | | 131.47 | | | | | | 155.65 | | | | | | 200.29 | | | | | | 163.98 | | | | | | 207.04 | | |

| S&P 500 Utility Index | | | 100.00 | | | | | | 126.35 | | | | | | 127.01 | | | | | | 149.46 | | | | | | 151.79 | | | | | | 141.05 | | |

| Philadelphia Utility Index | | | 100.00 | | | | | | 126.82 | | | | | | 130.27 | | | | | | 154.03 | | | | | | 155.03 | | | | | | 140.83 | | |

We have audited the accompanying consolidated balance sheet of Ameren Corporation and its subsidiaries (the “Company”) as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the related consolidated [removed: statements] [added: statement] of income and comprehensive income, of shareholders’ equity and of cash flows for each of the three years in the period ended December 31, [removed: 2023,] [added: 2024,] including the related notes and financial statement schedules listed in the index appearing under Item 15(a)(2) (collectively referred to as the “consolidated financial statements”).

We also have audited the Company’s internal control over financial reporting as of December 31, [removed: 2023,] [added: 2024,] based on criteria established in *Internal Control - Integrated Framework* (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the results of its operations and its cash flows for each of the three years in the period ended December 31, [removed: 2023] [added: 2024] in conformity with accounting principles generally accepted in the United States of America.

Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, [removed: 2023,] [added: 2024,] based on criteria established in *Internal Control - Integrated Framework* (2013) issued by the COSO.

As of December 31, [removed: 2023,] [added: 2024,] there were approximately [removed: $2.2] [added: $2.8] billion of regulatory assets and approximately [removed: $5.6] [added: $6.0] billion of regulatory liabilities.

These procedures included testing the effectiveness of controls relating to management’s implementation and application of new or existing regulatory assets or liabilities, including controls related to evaluating the probability of recovery of regulatory assets and refund of regulatory [removed: liabilities, and alternative revenue programs.][added: liabilities.]

These procedures also included, among others, (i) testing calculations of new and existing regulatory assets or liabilities by comparison to provisions and formulas outlined in regulatory commission orders or [removed: legislation,] [added: legislation and] (ii) evaluating management’s assessment of the probability of recovery of regulatory assets and refund of regulatory [removed: liabilities, and (iii) evaluating management’s assessment of regulatory mechanisms meeting the alternative revenue program criteria and the expected timing of collection within 24 months of the end of the annual period in which mechanisms are recognized.][added: liabilities.]

[removed: February 29, 2024][added: | | | | | | | 2024 | | |]

We have audited the accompanying consolidated balance sheet of Union Electric Company and its subsidiaries (the “Company”) as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the related consolidated [removed: statements] [added: statement] of income, of shareholders’ equity and of cash flows for each of the three years in the period ended December 31, [removed: 2023,] [added: 2024,] including the related notes and financial statement schedule listed in the index appearing under Item 15(a)(2) (collectively referred to as the “consolidated financial statements”).

In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the results of its operations and its cash flows for each of the three years in the period ended December 31, [removed: 2023] [added: 2024] in conformity with accounting principles generally accepted in the United States of America.

Those standards require that we plan and perform the [removed: audit] [added: audits] to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud.

As of December 31, [removed: 2023,] [added: 2024,] there were approximately [removed: $0.9] [added: $1.4] billion of regulatory assets and approximately [removed: $3.0] [added: $3.2] billion of regulatory liabilities.

The principal considerations for our determination that performing procedures relating to accounting for the effects of regulation is a critical audit matter are the significant judgment by management when accounting for (i) new or existing regulatory assets or liabilities that were [added: impacted by updates in regulatory commission orders, legislation, historical experience, or management’s discussions with legal counsel and]

We have audited the accompanying balance sheet of Ameren Illinois Company (the “Company”) as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the related [removed: statements] [added: statement] of income, of shareholders’ equity and of cash flows for each of the three years in the period ended December 31, [removed: 2023,] [added: 2024,] including the related notes and financial statement schedule listed in the index appearing under Item 15(a)(2) (collectively referred to as the “financial statements”).

In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, [removed: 2023] [added: 2024] and [removed: 2022,] [added: 2023,] and the results of its operations and its cash flows for each of the three years in the period ended December 31, [removed: 2023] [added: 2024] in conformity with accounting principles generally accepted in the United States of America.

Those standards require that we plan and perform the [removed: audit] [added: audits] to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.

As of December 31, [removed: 2023,] [added: 2024,] there were approximately $1.3 billion of regulatory assets and approximately [removed: $2.5] [added: $2.7] billion of regulatory liabilities.

| | | | [removed: 2023] [added: 2024] | | | | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2021] [added: 2022] | | |

| Electric | | | $ | [removed: 6,439] [added: 6,540] | | | | | $ | [removed: 6,581] [added: 6,439] | | | | | $ | [removed: 5,297] [added: 6,581] | |

| Natural gas | | | [removed: 1,061] [added: 1,083] | | | | | | [removed: 1,376] [added: 1,061] | | | | | | [removed: 1,097] [added: 1,376] | | |

| Total operating revenues | | | [removed: 7,500] [added: 7,623] | | | | | | [removed: 7,957] [added: 7,500] | | | | | | [removed: 6,394] [added: 7,957] | | |

| Natural gas purchased for resale | | | [removed: 355] [added: 320] | | | | | | [removed: 657] [added: 355] | | | | | | [removed: 442] [added: 657] | | |

| Other operations and maintenance | | | [removed: 1,866] [added: 1,969] | | | | | | [removed: 1,937] [added: 1,866] | | | | | | [removed: 1,774] [added: 1,937] | | |

| Depreciation and amortization | | | [removed: 1,387] [added: 1,590] | | | | | | [removed: 1,289] [added: 1,387] | | | | | | [removed: 1,146] [added: 1,289] | | |

| Taxes other than income taxes | | | [removed: 522] [added: 547] | | | | | | [removed: 539] [added: 522] | | | | | | [removed: 512] [added: 539] | | |

| Total operating expenses | | | [removed: 5,942] [added: 6,107] | | | | | | [removed: 6,442] [added: 5,942] | | | | | | [removed: 5,061] [added: 6,442] | | |

| Operating Income | | | [removed: 1,558] [added: 1,516] | | | | | | [removed: 1,515] [added: 1,558] | | | | | | [removed: 1,333] [added: 1,515] | | |

| Other Income, Net | | | [removed: 348] [added: 417] | | | | | | [removed: 226] [added: 348] | | | | | | [removed: 202] [added: 226] | | |

| Interest Charges | | | [removed: 566] [added: 663] | | | | | | [removed: 486] [added: 566] | | | | | | [removed: 383] [added: 486] | | |

| Income Before Income Taxes | | | [removed: 1,340] [added: 1,270] | | | | | | [removed: 1,255] [added: 1,340] | | | | | | [removed: 1,152] [added: 1,255] | | |

| Income Taxes | | | [removed: 183] [added: 83] | | | | | | [removed: 176] [added: 183] | | | | | | [removed: 157] [added: 176] | | |

| Net Income | | | [removed: 1,157] [added: 1,187] | | | | | | [removed: 1,079] [added: 1,157] | | | | | | [removed: 995] [added: 1,079] | | |

| Net Income Attributable to Ameren Common Shareholders | | | $ | [removed: 1,152] [added: 1,182] | | | | | $ | [removed: 1,074] [added: 1,152] | | | | | $ | [removed: 990] [added: 1,074] | |

| Net Income | | | $ | [removed: 1,157] [added: 1,187] | | | | | $ | [removed: 1,079] [added: 1,157] | | | | | $ | [removed: 995] [added: 1,079] | |

| Pension and other postretirement benefit plan activity, net of income taxes (benefit) of [added: $—,] $(2), [removed: $(4),] and [removed: $4,] [added: $(4),] respectively | | | [removed: (5)] [added: (3)] | | | | | | [removed: (14)] [added: (5)] | | | | | | [removed: 14] [added: (14)] | | |