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

This MDA includes information relating to Alliant Energy, and IPL and WPL (collectively, the Utilities), as well as ATC Holdings, AEF and Corporate Services. Where appropriate, information relating to a specific entity has been segregated and labeled as such. The following discussion and analysis should be read in conjunction with the Financial Statements and the Notes included in this report, as well as the financial statements, notes and MDA included in the 2024 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2025 HIGHLIGHTS

Key highlights since the filing of the 2024 Form 10-K include the following:

Customer Investments:

• Over the next six years, Alliant Energy currently plans to develop and/or acquire new generation investments to add flexibility with evolving load growth, including approximately 1,500 MW of new natural gas resources, approximately 1,200 MW of new wind generation, approximately 800 MW of new energy storage, refurbishments at approximately 500 MW of existing wind farms, improvements of approximately 280 MW at existing natural gas-fired EGUs, and the conversion of existing coal-fired EGUs to natural gas. Alliant Energy is currently evaluating the impact of potential additional large load growth customers and MISO’s seasonal resource adequacy requirements on its resource plans and will update these generation investment plans as needed in the future. Estimated capital expenditures for these planned projects for 2025 through 2028 are included in the “Generation” section in the construction and acquisition table in “Liquidity and Capital Resources.” Information on IPL’s and WPL’s regulatory filings and/or approvals for future generation and energy storage projects are as follows:

• In February 2025, WPL filed a certificate of authority (CA) application with the PSCW for approval to construct a 2 billion cubic feet, or 25 million gallon, liquified natural gas facility in Rock County, Wisconsin. A decision from the PSCW is currently expected in the second quarter of 2026.

• In April 2025, the PSCW issued an order authorizing WPL to construct, own and operate a 17.5 MW natural gas-fired EGU using Reciprocating Internal Combustion Engine (RICE) technology, at the site of its Riverside Energy Center.

• In April 2025, WPL filed a CA application with the PSCW for approval to construct, own and operate the Bent Tree North EGU, an approximate 153 MW wind farm. A decision from the PSCW is currently expected in the second quarter of 2026.

• In May 2025, the PSCW issued an order authorizing WPL to refurbish the Bent Tree wind farm.

• In May 2025, IPL filed a certificate of public convenience, use and necessity (GCU Certificate) application with the IUC for approval to construct, own and operate up to 75 MW of energy storage at the site of its Golden Plains wind farm. A decision from the IUC is currently expected in the fourth quarter of 2025.

• In May 2025, IPL filed a GCU Certificate application with the IUC for approval to construct, own and operate up to 75 MW of energy storage at the site of its Whispering Willow - North wind farm. A decision from the IUC is currently expected in the fourth quarter of 2025.

• In June 2025, the IUC issued an order authorizing IPL to construct, own and operate the Cedar River Generating Station, a 94 MW natural gas-fired EGU using RICE technology, at the site of its Prairie Creek Generating Station.

• In June 2025, the PSCW issued an order authorizing WPL to construct, own and operate an approximately 20 MW compressed carbon dioxide-based long-duration energy storage system at the site of its Columbia Energy Center.

• In July 2025, IPL filed for advance rate-making principles with the IUC for up to 1,000 MW of new wind generation in Iowa. The advance rate-making principles filing included requests for a fixed cost cap of $3,020/kilowatt, including allowance for funds used during construction and transmission upgrade costs among other costs, and a return on common equity of 11.25%. A decision from the IUC is currently expected in the first quarter of 2026.

• In July 2025, the IUC issued an order authorizing IPL to construct, own and operate up to 150 MW of energy storage at the site of its retired Lansing Generating Station.

• In July 2025, WPL completed construction of approximately 100 MW of energy storage at the site of its Grant County solar facility.

Rate Matters:

• In March 2025, WPL filed a retail electric and gas rate review with the PSCW for the 2026/2027 forward-looking Test Period. The key drivers for the filing include revenue requirement impacts of increasing electric and gas rate base, including wind refurbishment projects, energy storage, existing natural gas-fired EGU improvements, solar generation costs incurred that exceed the construction cost estimates previously approved by the PSCW, and electric and gas distribution investments. The filing requested approval for WPL to implement increases in annual rates for its retail electric and gas customers of $120 million and $9 million in 2026, respectively, with any granted rate changes expected to be effective on January 1, 2026. WPL’s filing also requested approval to implement an additional increase in annual rates for its retail electric and gas customers of $82 million and $5 million in 2027, respectively, with any granted rate changes expected to be effective on January 1, 2027. WPL also requested a return on common equity of 9.9% and to implement a common equity component of its regulatory capital structure of 55.5% in 2026 and 55.3% in 2027. WPL’s filing also requested an extension, with certain modifications, of its current earnings sharing mechanism through 2027, including deferral of a portion of its earnings if its annual regulatory return on common equity exceeds 10.15% during the 2026/2027 Test Period (deferral of 50% of its excess earnings between 10.15% and 10.65%, and 100% of any excess earnings above 10.65%). A decision from the PSCW is currently expected by the end of 2025.

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Growing Customer Demand:

• WPL has entered into an electric service agreement with a new customer, who currently expects to build a data center at the Beaver Dam Commerce Park in Beaver Dam, Wisconsin in WPL’s service territory. The actual timing and amount of increases in WPL’s load are subject to various factors, including interconnections and actual customer demand, and any executed or future agreements with customers are not expected to result in immediate increases in load. IPL’s and WPL’s currently executed electric service agreements include aggregate, maximum demands of approximately 2.1 gigawatts.

• In May 2025, the IUC issued an order, with certain conditions, approving individual customer rates associated with certain of the data centers expected to be constructed in IPL’s service territory. In June 2025 and April 2025, IPL and WPL filed requests with the IUC and PSCW, respectively, for approval of the individual customer rates associated with certain of the data centers expected to be constructed in their service territories, with decisions from the IUC and PSCW currently expected by the end of the third quarter of 2025.

Environmental Matters and Stewardship:

• In March 2025, the EPA announced it expects to initiate a formal reconsideration of various environmental regulations and programs, including the Cross-State Air Pollution Rule and Effluent Limitation Guidelines. In June 2025, the EPA proposed to repeal Clean Air Act Sections 111(b) and 111(d). In July 2025, the EPA proposed to repeal its 2009 ruling that found GHG contributes to climate change and gave it authority to regulate GHG under the Clean Air Act. The EPA also expects to expedite review of state programs to delegate implementation of the Coal Combustion Residuals Rule and reconsider compliance deadlines. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters, including resolution of ongoing and potential litigation.

• Alliant Energy’s current voluntary environmental stewardship goals include the following:

• By 2030, reduce GHG emissions from its utility operations by 50% from 2005 levels, reduce its electric utility water supply by 75% from 2005 levels and electrify 100% of its owned light-duty fleet vehicles.

• By 2040, eliminate all coal-fired EGUs from its generating fleet.

• By 2050, aspire to achieve net-zero GHG emissions from its utility operations.

• Alliant Energy’s aspirational GHG goal includes EPA reportable emissions based on applicable regulatory compliance requirements for carbon dioxide, methane and nitrous oxide from its owned fossil-fueled EGUs and distribution of natural gas. Alliant Energy’s voluntary environmental stewardship goals may be revised, or their achievement may be delayed, based on increasing customer energy needs, reliability and resource adequacy requirements, and tax policy changes, and the ability to achieve these goals is subject to various additional risk factors included in the 2024 Form 10-K. These goals are not meant to be considered guidance.

Legislative Matters:

• In July 2025, the One Big Beautiful Bill Act was enacted, which modifies various clean energy tax credits under the Inflation Reduction Act of 2022, including production tax credits and investment tax credits. The most significant provisions of the new legislation for Alliant Energy, IPL and WPL relate to the accelerated phase out of clean energy tax credits for eligible projects for which construction begins more than 12 months after the date of enactment or for projects placed in service after 2027, and restricted access to clean energy tax credits for projects that begin construction after 2025 and receive impermissible amounts of construction support from entities with ties to certain foreign countries, including China. Additionally, in July 2025, the Presidential Administration directed the U.S. Department of the Treasury to strictly enforce the termination of clean energy tax credits, including issuing new and revised guidance by September 2025, to ensure that requirements concerning the beginning of construction are not circumvented. Refer to “2025 Highlights” for discussion of Alliant Energy’s, IPL’s and WPL’s current plans to develop and/or acquire new clean energy resources. Alliant Energy, IPL and WPL currently expect these clean energy projects would continue to be eligible for clean energy tax credits. If these clean energy projects do not begin construction within the anticipated timeframes or fail to meet other eligibility requirements, the amount of clean energy tax credits could be significantly reduced, which could adversely impact Alliant Energy’s, IPL’s and WPL’s financial condition and results of operations.

Financings:

• Refer to “Results of Operations” for discussion of expected future issuances and retirements of long-term debt in 2025.

• In April 2025, WPL submitted an application to the U.S. Army Corps of Engineers for up to $45 million in loans through the Corps Water Infrastructure Financing Program. If finalized, such loans would provide low interest financing for various proposed safety projects at WPL’s Kilbourn and Prairie du Sac hydro EGUs.

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RESULTS OF OPERATIONS

Financial Results Overview - The table below includes diluted EPS for Utilities and Corporate Services, ATC Holdings, and Non-utility and Parent, which are non-GAAP financial measures. Alliant Energy believes these non-GAAP financial measures are useful to investors because they facilitate an understanding of performance and trends, and provide additional information about Alliant Energy’s operations on a basis consistent with the measures that management uses to manage its operations and evaluate its performance. Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended June 30 were as follows (dollars in millions, except per share amounts):

			2025												2024
			Income (Loss)						EPS						Income (Loss)						EPS
Utilities and Corporate Services			$190						$0.74						$85						$0.33
ATC Holdings			10						0.04						9						0.04
Non-utility and Parent			(26)						(0.10)						(7)						(0.03)
Alliant Energy Consolidated			$174						$0.68						$87						$0.34

Alliant Energy’s Utilities and Corporate Services net income increased by $105 million for the three-month period, primarily due to higher revenue requirements from IPL’s and WPL’s capital investments, an asset valuation charge in 2024 for IPL’s retired Lansing Generating Station, an ARO charge in 2024 allocated to the steam business at IPL due to the revised Coal Combustion Residuals Rule, and estimated temperature impacts on retail electric and gas sales. These items were partially offset by higher depreciation and financing expenses.

Alliant Energy’s Non-utility and Parent net income decreased $19 million for the three-month period, primarily due to lower equity income from corporate venture investments, higher financing expense and the timing of income taxes.

Net Income Variances - The following items contributed to increased (decreased) net income for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Revenues:
Changes in electric utility (Refer to details below)			$62						$14						$48						$123						$53						$70
Changes in gas utility (Refer to details below)			7						—						7						43						10						33
Changes in other utility			1						2						(1)						1						1						—
Changes in non-utility			(3)						—						—						(4)						—						—
Changes in total revenues			67						16						54						163						64						103
Operating expenses:
Changes in electric production fuel and purchased power (Refer to details below)			(12)						8						(20)						(24)						9						(32)
Changes in electric transmission service (Refer to details below)			(4)						(1)						(2)						(8)						(5)						(3)
Changes in cost of gas sold (Refer to details below)			(5)						—						(5)						(28)						(4)						(24)
Asset valuation charge for IPL’s Lansing Generating Station in 2024 (Refer to Note 2 for details)			60						60						—						60						60						—
Changes in other operation and maintenance (Refer to details below)			9						18						(5)						9						18						(9)
Changes in depreciation and amortization (Higher primarily due to solar generation placed in service in 2024 and updated electric depreciation rates for IPL effective October 1, 2024)			(20)						(18)						(3)						(44)						(37)						(5)
Changes in taxes other than income taxes			(2)						(1)						(1)						(1)						1						(1)
Changes in total operating expenses			26						66						(36)						(36)						42						(74)
Changes in operating income			93						82						18						127						106						29
Other income and deductions:
Changes in interest expense (Higher primarily due to financings completed in 2024 and 2025)			(16)						(10)						(2)						(28)						(15)						(4)
Changes in equity income from unconsolidated investments, net (Refer to Note 4 for details)			(5)						—						—						(8)						—						—
Changes in allowance for funds used during construction			4						2						2						3						1						2
Changes in Other			1						2						(3)						—						2						(3)
Changes in total other income and deductions			(16)						(6)						(3)						(33)						(12)						(5)
Changes in income before income taxes			77						76						15						94						94						24
Changes in income taxes (Refer to Note 8 for details)			10						4						8						48						34						18
Changes in net income			$87						$80						$23						$142						$128						$42

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Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three and six months ended June 30 were as follows:

Alliant Energy			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2025						2024						2025						2024						2025						2024						2025						2024
Three Months
Retail			$746						$719						5,926						5,948						$64						$59						6,114						5,730
Sales for resale:
Wholesale			49						43						651						653						N/A						N/A						N/A						N/A
Bulk power and other			43						13						1,176						1,087						N/A						N/A						N/A						N/A
Transportation/Other			13						14						14						14						12						10						27,159						29,102
			$851						$789						7,767						7,702						$76						$69						33,273						34,832
Six Months
Retail			$1,518						$1,425						12,100						11,937						$290						$251						29,936						25,848
Sales for resale:
Wholesale			97						89						1,342						1,333						N/A						N/A						N/A						N/A
Bulk power and other			69						34						2,554						2,757						N/A						N/A						N/A						N/A
Transportation/Other			19						32						28						29						26						22						58,165						63,009
			$1,703						$1,580						16,024						16,056						$316						$273						88,101						88,857

IPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2025						2024						2025						2024						2025						2024						2025						2024
Three Months
Retail			$395						$387						3,286						3,291						$33						$34						2,667						2,679
Sales for resale:
Wholesale			14						13						161						173						N/A						N/A						N/A						N/A
Bulk power and other			1						(2)						301						205						N/A						N/A						N/A						N/A
Transportation/Other			8						6						8						8						7						6						10,295						9,590
			$418						$404						3,756						3,677						$40						$40						12,962						12,269
Six Months
Retail			$804						$762						6,724						6,656						$142						$135						14,439						12,885
Sales for resale:
Wholesale			28						26						343						356						N/A						N/A						N/A						N/A
Bulk power and other			2						(5)						697						529						N/A						N/A						N/A						N/A
Transportation/Other			14						12						16						16						16						13						22,366						21,284
			$848						$795						7,780						7,557						$158						$148						36,805						34,169

WPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2025						2024						2025						2024						2025						2024						2025						2024
Three Months
Retail			$351						$332						2,640						2,657						$31						$25						3,447						3,051
Sales for resale:
Wholesale			35						30						490						480						N/A						N/A						N/A						N/A
Bulk power and other			42						15						875						882						N/A						N/A						N/A						N/A
Transportation/Other			5						8						6						6						5						4						16,864						19,512
			$433						$385						4,011						4,025						$36						$29						20,311						22,563
Six Months
Retail			$714						$663						5,376						5,281						$148						$116						15,497						12,963
Sales for resale:
Wholesale			69						63						999						977						N/A						N/A						N/A						N/A
Bulk power and other			67						39						1,857						2,228						N/A						N/A						N/A						N/A
Transportation/Other			5						20						12						13						10						9						35,799						41,725
			$855						$785						8,244						8,499						$158						$125						51,296						54,688

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Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes were unchanged and increased 1% for the three and six months ended June 30, 2025, respectively, compared to the same periods in 2024, primarily due to changes in temperatures. Alliant Energy’s retail gas sales volumes increased 7% and 16% for the three and six months ended June 30, 2025, respectively, compared to the same periods in 2024, primarily due to changes in temperatures.

Estimated increases (decreases) to operating income from the impacts of temperatures for the three and six months ended June 30 were as follows (in millions):

			Electric																																				Gas
			Three Months																		Six Months																		Three Months																		Six Months
			2025						2024						Change						2025						2024						Change						2025						2024						Change						2025						2024						Change
IPL			$4						$1						$3						$—						($8)						$8						($1)						($1)						$—						($3)						($7)						$4
WPL			3						(2)						5						—						(12)						12						—						(2)						2						(1)						(7)						6
Total Alliant Energy			$7						($1)						$8						$—						($20)						$20						($1)						($3)						$2						($4)						($14)						$10

Electric Sales for Resale - Bulk Power and Other - Bulk power and other volume changes were due to changes in sales in the wholesale energy markets operated by MISO. These changes are impacted by several factors, including the availability and dispatch of Alliant Energy’s EGUs and electricity demand within these wholesale energy markets. Changes in bulk power and other revenues were largely offset by changes in fuel-related costs, and therefore did not have a significant impact on operating income.

Gas Transportation/Other - Gas transportation/other sales volume changes were largely due to changes in the gas volumes supplied to Alliant Energy’s natural gas-fired EGUs caused by the availability and dispatch of such EGUs.

Electric Utility Revenue Variances - The following items contributed to increased (decreased) electric utility revenues for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Higher revenue requirements (a)(b)			$94						$79						$15						$202						$172						$30
Higher sales for resale bulk power and other revenues (c)			30						3						27						35						7						28
Estimated changes in sales volumes caused by temperatures			8						3						5						20						8						12
Changes in WPL electric fuel-related costs, net of recoveries (d)			11						—						11						6						—						6
Lower revenues at IPL due to credits on customers’ bills related to production tax credits through its fuel-related cost recovery mechanism (offset by changes in income taxes) (a)			(38)						(38)						—						(89)						(89)						—
Lower revenues at IPL due to credits on customers’ bills through the tax benefit rider in 2025 (partially offset by changes in income taxes) (a)			(16)						(16)						—						(34)						(34)						—
Higher (lower) revenues primarily due to changes in retail electric fuel-related costs (Refer to Electric Production Fuel and Purchased Power Expenses Variances below)			(25)						(18)						(7)						(14)						(18)						4
Other			(2)						1						(3)						(3)						7						(10)
			$62						$14						$48						$123						$53						$70

(a)In September 2024, the IUC issued an order authorizing an annual base rate increase of $185 million for IPL’s retail electric customers, with customers receiving partially offsetting credits for the first 12 months through a tax benefit rider, for the October 2024 through September 2025 forward-looking Test Period. Rate changes were effective October 1, 2024, which reflect revenue requirement impacts of increasing electric rate base including investments in solar generation, updated depreciation rates, and certain incremental costs incurred resulting from the 2020 derecho windstorm. In addition, effective October 1, 2024, IPL’s renewable energy rider was discontinued, and certain production tax credits are credited to IPL’s retail electric customers through IPL’s fuel-related cost recovery mechanism. Credits on IPL’s customers’ bills have been and are expected to be offset by a reduction in income tax expense.

(b)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $60 million for WPL’s retail electric customers, covering the 2025 forward-looking Test Period, which reflects revenue requirement impacts of increasing electric rate base including investments in solar generation and energy storage.

(c)Alliant Energy’s and WPL’s sales for resale bulk power and other revenues increased primarily due to higher prices for electricity and capacity sold by WPL to MISO wholesale energy markets. These changes were largely offset by changes in fuel-related costs.

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(d)WPL’s cost recovery mechanism for retail fuel-related expenses supports deferrals of amounts that fall outside an approved fuel monitoring range of forecasted fuel-related expenses determined by the PSCW each year. The difference between revenue collected and actual fuel-related expenses incurred within the fuel monitoring range increases or decreases Alliant Energy’s and WPL’s electric utility revenues. WPL estimates the increase (decrease) to electric utility revenues from amounts within the fuel monitoring range were approximately $6 million and $2 million for the three and six months ended June 30, 2025, respectively, compared to ($5) million and ($4) million for the three and six months ended June 30, 2024, respectively.

Gas Utility Revenue Variances - The following items contributed to increased (decreased) gas utility revenues for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Higher revenues due to changes in gas costs (Refer to Cost of Gas Sold Expense Variances below)			$5						$—						$5						$28						$4						$24
Estimated changes in sales volumes caused by temperatures			2						—						2						10						4						6
Higher revenue requirements (a)			1						1						—						5						5						—
Other			(1)						(1)						—						—						(3)						3
			$7						$—						$7						$43						$10						$33

(a)In September 2024, the IUC issued an order authorizing an annual base rate increase of $10 million for IPL’s retail gas customers, for the October 2024 through September 2025 forward-looking Test Period. Rate changes were effective October 1, 2024, which reflect revenue requirement impacts of increasing gas rate base.

Electric Production Fuel and Purchased Power Expenses Variances - The following items contributed to (increased) decreased electric production fuel and purchased power expenses for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Higher electric production fuel costs (a)			($21)						($12)						($9)						($27)						($17)						($10)
Lower (higher) purchased power expense (b)			4						2						2						(10)						4						(14)
Changes in regulatory recovery of retail electric fuel-related costs			8						19						(11)						13						22						(9)
Other			(3)						(1)						(2)						—						—						1
			($12)						$8						($20)						($24)						$9						($32)

(a)Electric production fuel costs increased for the three and six months ended June 30, 2025, compared to the same periods in 2024, primarily due to higher coal volumes due to higher dispatch of coal-fired EGUs and higher natural gas prices, partially offset by lower natural gas volumes due to lower dispatch of natural gas-fired EGUs.

(b)Purchased power expense increased for the six months ended June 30, 2025 compared to the same period in 2024, primarily due to higher prices for electricity purchased at WPL.

Electric Transmission Service Expense Variances - The following items contributed to (increased) decreased electric transmission service expense for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Changes in regulatory recovery for the difference between actual electric transmission service costs and those costs used to determine rates			$4						$1						$3						$7						$1						$6
Other (primarily due to changes in transmission service costs provided by third parties)			(8)						(2)						(5)						(15)						(6)						(9)
			($4)						($1)						($2)						($8)						($5)						($3)

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Cost of Gas Sold Expense Variances - The following items contributed to (increased) decreased cost of gas sold expense for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Higher retail gas volumes and changes in natural gas prices			($10)						($1)						($9)						($22)						($6)						($16)
Changes in the regulatory recovery of gas costs			5						1						4						(6)						2						(8)
			($5)						$—						($5)						($28)						($4)						($24)

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
ARO charge in 2024 for steam assets at IPL (Refer to Note 1(c) for details)			$20						$20						$—						$20						$20						$—
Other (primarily due to higher generation expense)			(11)						(2)						(5)						(11)						(2)						(9)
			$9						$18						($5)						$9						$18						($9)

Other Future Considerations - In addition to items discussed in this report, the following key items could impact Alliant Energy’s, IPL’s and WPL’s future financial condition or results of operations:

• Financing Plans** - Alliant Energy currently expects to issue up to $1.3 billion of common stock in aggregate from 2026 through 2028 through the distribution agreement that was executed in May 2025, and up to $25 million of common stock annually through its Shareowner Direct Plan in 2025 through 2028. For the remainder of 2025, IPL and WPL currently expect to issue up to $400 million and $300 million, respectively, of long-term debt, and AEF and/or Alliant Energy at the parent company level expect to issue up to $725 million of long-term debt in aggregate. IPL has $250 million of long-term debt maturing in August 2025.

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2024 Form 10-K has not changed materially, except as described below.

Liquidity Position - At June 30, 2025, Alliant Energy had $329 million of cash and cash equivalents, $1,008 million ($550 million at the parent company, $350 million at IPL and $108 million at WPL) of available capacity under the single revolving credit facility and $4 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Financial capital structures at June 30, 2025 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE)):

Cash Flows - Selected information from the cash flows statements was as follows (in millions):

			Alliant Energy												IPL												WPL
			2025						2024						2025						2024						2025						2024
Cash, cash equivalents and restricted cash, January 1			$81						$63						$29						$53						$51						$7
Cash flows from (used for):
Operating activities			492						562						108						147						337						391
Investing activities			(894)						(533)						(441)						(209)						(362)						(247)
Financing activities			650						1						508						18						(16)						(71)
Net increase (decrease)			248						30						175						(44)						(41)						73
Cash, cash equivalents and restricted cash, June 30			$329						$93						$204						$9						$10						$80

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Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):

			Alliant Energy						IPL						WPL
Lower collections from IPL’s retail customers due to credits on customers’ bills related to production tax credits through its fuel-related cost recovery mechanism			($89)						($89)						$—
Lower collections from IPL’s retail customers due to credits on customers’ bills related to the tax benefit rider			(34)						(34)						—
Changes in interest payments			(32)						(12)						(12)
Restructuring and voluntary employee separation payments in 2025			(25)						(11)						(12)
Higher collections from IPL’s and WPL’s retail electric and IPL’s gas base rate increases			207						177						30
Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales			30						12						18
Changes in income taxes paid/received (a)			2						(24)						18
Other (primarily due to other changes in working capital)			(129)						(58)						(96)
			($70)						($39)						($54)

(a)Refer to the cash flows statements for details of renewable tax credits transferred to other corporate taxpayers during the six months ended June 30, 2025 and 2024.

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):

			Alliant Energy						IPL						WPL
Proceeds from sales of partial ownership interests in West Riverside in 2024			($123)						$—						($123)
Changes in the amount of cash receipts on sold receivables			(108)						(108)						—
(Higher) lower utility construction and acquisition expenditures (a)			(106)						(128)						22
Other			(24)						4						(14)
			($361)						($232)						($115)

(a)Largely due to higher expenditures for IPL’s energy storage, partially offset by lower expenditures for IPL’s and WPL’s solar generation.

Construction and Acquisition Expenditures - Construction and acquisition expenditures and financing plans are reviewed, approved and updated as part of the strategic planning process. Changes may result from a number of reasons, including changes in expected load growth, regulatory requirements, changing legislation, not obtaining favorable and acceptable regulatory approval on certain projects, changing costs of projects due to market conditions and the impact of tariffs, improvements in technology, and improvements to ensure resiliency and reliability of the electric and gas distribution systems. Alliant Energy, IPL and WPL have not yet entered into contractual commitments relating to the majority of their anticipated future construction and acquisition expenditures. As a result, they have some discretion with regard to the level and timing of these expenditures. Construction and acquisition expenditures for 2025 through 2028 are currently anticipated as follows (in millions), which are focused on adding generation to meet growing customer demand for electricity, including expected future data center growth from currently executed electric service agreements, and strengthening the resiliency and reliability of the electric grid, and include renewable generation and energy storage projects, dispatchable gas generation projects, and converting certain coal-fired EGUs to natural gas. Alliant Energy, IPL and WPL are currently evaluating the impacts of tariffs, recently enacted legislation and additional potential large load growth customers on their resource plans, and will update their anticipated construction and acquisition expenditures as needed in the future. Cost estimates represent Alliant Energy’s, IPL’s and WPL’s portion of construction expenditures and exclude allowance for funds used during construction and capitalized interest, if applicable.

			Alliant Energy															IPL															WPL
			2025			2026			2027			2028									2025			2026			2027			2028									2025			2026			2027			2028
Generation:
Renewables and energy storage projects			$995			$895			$1,125			$1,160									$675			$480			$580			$660									$320			$415			$545			$500
Gas projects			460			740			1,025			885									240			320			615			645									170			385			410			240
Other			145			135			70			65									65			60			30			15									80			75			40			50
Distribution:
Electric systems			595			625			600			580									325			265			250			255									270			360			350			325
Gas systems			100			130			160			105									55			70			90			40									45			60			70			65
Other			215			230			225			245									45			35			45			50									35			30			35			25
			$2,510			$2,755			$3,205			$3,040									$1,405			$1,230			$1,610			$1,665									$920			$1,325			$1,450			$1,205

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Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):

			Alliant Energy						IPL						WPL
Lower payments to retire long-term debt			$305						$—						$—
Higher (lower) net proceeds from issuance of long-term debt			193						594						(297)
Net changes in the amount of commercial paper outstanding			157						(50)						427
Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy			—						20						(55)
Higher common stock dividends			(15)						(80)						(21)
Other			9						6						1
			$649						$490						$55

Common Stock Issuances - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2025 and Alliant Energy’s at-the-market offering program. Refer to “Results of Operations” for discussion of expected future issuances of common stock from 2025 through 2028.

Long-term Debt - Refer to Note 6(b) for discussion of AEF’s term loan credit agreements and various issuances and/or retirements of long-term debt by Alliant Energy and IPL in 2025. Refer to “Results of Operations” for discussion of expected future issuances and retirements of long-term debt in 2025.

Impact of Credit Ratings on Liquidity and Collateral Obligations -

Ratings Triggers - In March 2025, Standard & Poor’s Ratings Services changed certain Alliant Energy, IPL and WPL credit ratings and outlooks, which are not expected to have a material impact on Alliant Energy’s, IPL’s and WPL’s liquidity or collateral obligations, and the current credit ratings and outlooks are as follows:

						Standard & Poor’s Ratings Services
Alliant Energy:			Corporate/issuer			BBB+
			Commercial paper			A-2
			Senior unsecured long-term debt			BBB
			Outlook			Stable
IPL:			Corporate/issuer			BBB+
			Commercial paper			A-2
			Senior unsecured long-term debt			BBB+
			Outlook			Stable
WPL:			Corporate/issuer			A-
			Commercial paper			A-2
			Senior unsecured long-term debt			A-
			Outlook			Stable

Off-Balance Sheet Arrangements and Certain Financial Commitments - A summary of Alliant Energy’s and IPL’s off-balance sheet arrangements and Alliant Energy’s, IPL’s and WPL’s contractual obligations is included in the 2024 Form 10-K and has not changed materially from the items reported in the 2024 Form 10-K, except for the items described in Notes 3, 6 and 12.