Alliant Energy Corp: Form 10-Q for the period ended Mar 31, 2026

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 2025 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2026 HIGHLIGHTS

Key highlights since the filing of the 2025 Form 10-K include the following:

Customer Investments:

• In March 2026, the IUC approved advance rate-making principles for IPL for up to 1,000 MW of new wind generation in Iowa. The rate-making principles approved include a fixed cost cap of $3,020/kilowatt, including AFUDC and transmission costs, among other costs. IPL’s return on common equity will be the same as other assets without advance rate-making principles for the purposes of setting future rates and IPL’s blended return on common equity, which will be updated each year, will be used for IPL’s retail electric earnings sharing mechanism calculation.
• In March 2026, WPL filed a certificate of authority application with the PSCW for approval to construct, own and install equipment that will maintain and increase the capacity and efficiency of its Riverside Energy Center. A decision from the PSCW is currently expected in the first quarter of 2027.
• In April 2026, IPL filed a certificate of public convenience, use and necessity application with the IUC for approval to construct, own and operate an approximately 720 MW simple-cycle natural gas-fired EGU in Linn County, Iowa. A decision from the IUC is currently expected in the first quarter of 2027.

Growing Customer Demand:

• In April 2026, IPL entered into an electric service agreement with a customer, who currently expects to build a data center in IPL’s service territory. This electric service agreement includes contracted peak demand of approximately 370 MW. The actual timing and amount of increases in IPL’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.

Environmental Matters:

Coal Combustion Residuals (CCR) Rule - In April 2026, the EPA proposed a rule that would significantly reduce the scope of the CCR Rule, which is currently anticipated to be finalized by the end of 2026. Alliant Energy, IPL and WPL continue to evaluate the revised CCR Rule and are unable to predict with certainty the future outcome or impact of these updates, including resolution of ongoing litigation.

Legislative Matters:

• In April 2026, the State of Wisconsin enacted 2025 Wisconsin Act 193, which requires utilities to include their capacity costs and revenues in their annual fuel cost plans. The most significant provisions of the legislation for Alliant Energy and WPL are the requirement that fuel cost calculations in approved fuel cost plans account for both the cost of purchasing capacity and the revenue generated from selling it. The legislation applies to fuel cost plans filed on or after January 1, 2027.

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 diluted EPS attributable to Alliant Energy common shareowners for the three months ended March 31 were as follows (dollars in millions, except per share amounts):

Alliant Energy’s Utilities and Corporate Services net income decreased by $10 million for the three-month period, primarily due to higher other operation and maintenance, financing and depreciation expenses and the timing of income taxes. These items were partially offset by higher revenue requirements from IPL’s and WPL’s capital investments and higher AFUDC.

Alliant Energy’s Non-utility and Parent net income increased $20 million for the three-month period, primarily due to a state income tax apportionment benefit (refer to Note 8 for details) and the timing of income taxes.

Net Income Variances - The following items contributed to increased (decreased) net income for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three months ended March 31 were as follows:

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Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes decreased 1% for the three months ended March 31, 2026, compared to the same period in 2025, primarily due to changes in temperatures. Alliant Energy’s retail gas sales volumes decreased 6% for the three months ended March 31, 2026, compared to the same period in 2025, primarily due to changes in temperatures.

Estimated increases (decreases) to operating income from the impacts of temperatures for the three months ended March 31 were as follows (in millions):

Electric Sales for Resale - Alliant Energy’s and IPL’s wholesale sales volumes decreased for the three months ended March 31, 2026, compared to the same period in 2025, primarily due to the expiration of IPL’s wholesale power agreement with Southern Minnesota Energy Cooperative in 2025.

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 months ended March 31, 2026 compared to the same period in 2025 (in millions):

(a) In December 2025, the PSCW issued an order authorizing an annual base rate increase of $69 million for WPL’s retail electric customers, covering the 2026 forward-looking Test Period, which reflects revenue requirement impacts of increasing electric rate base, including wind refurbishment projects, energy storage, existing natural gas-fired EGU improvements and electric distribution investments and lower forecasted fuel-related expenses.

(b) Sales for resale bulk power and other revenues increased primarily due to higher volumes and higher prices for electricity sold by IPL and WPL to MISO wholesale energy markets. These changes were largely offset by changes in fuel-related costs.

Gas Utility Revenue Variances - The following items contributed to increased (decreased) gas utility revenues for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

(a) In December 2025, the PSCW issued an order authorizing an annual base rate increase of $7 million for WPL’s retail gas customers, covering the 2026 forward-looking Test Period, which reflects 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 months ended March 31, 2026 compared to the same period in 2025 (in millions):

(a) Purchased power expense decreased for the three months ended March 31, 2026 compared to the same period in 2025, primarily due to lower prices for electricity purchased and lower volumes purchased at IPL and WPL.

(b) Electric production fuel costs increased for the three months ended March 31, 2026 compared to the same period in 2025, primarily due to higher natural gas volumes due to higher dispatch of natural gas-fired EGUs and higher natural gas prices.

Cost of Gas Sold Expense Variances - The following items contributed to (increased) decreased cost of gas sold expense for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2025 Form 10-K has not changed materially, except as described below.

Liquidity Position - At March 31, 2026, Alliant Energy had $115 million of cash and cash equivalents, $817 million ($268 million at the parent company, $249 million at IPL and $300 million at WPL) of available capacity under the single revolving credit facility and $40 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - The following table shows financial capital structures as of March 31, 2026, as well as an adjusted capitalization structure that Alliant Energy believes is consistent with how a majority of the rating agencies currently view its junior subordinated notes (in millions):

(a) The long-term debt component of Alliant Energy’s financial capital structure includes junior subordinated notes classified as “Long-term debt, net” on Alliant Energy’s balance sheet. The adjusted presentation attributes 50% of the junior subordinated notes to common equity and 50% to long-term debt, to align with the debt-to-capital ratio used by the majority of rating agencies. The non-GAAP adjusted presentation reflecting this treatment is useful and relevant to investors in understanding how management and the rating agencies evaluate Alliant Energy’s capital structure.

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

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

(a) Refer to the cash flows statements for details of renewable tax credits transferred to other corporate taxpayers during the three months ended March 31, 2026.

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

(a) Largely due to lower expenditures for IPL’s energy storage and WPL’s gas generation.

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the three months ended March 31, 2026 compared to the same period in 2025 (in millions):

Common Stock Issuances - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2026 and Alliant Energy’s at-the-market offering programs.

Short-term Debt - Refer to Note 6(a) for discussion of Alliant Energy’s term loan credit agreement entered into in 2026.

Long-term Debt - Refer to Note 6(b) for discussion of issuances and/or retirements of long-term debt by Alliant Energy, AEF and IPL in 2026.

Impact of Credit Ratings on Liquidity and Collateral Obligations -

Ratings Triggers - In March 2026, Standard & Poor’s Ratings Services changed certain IPL credit ratings, which are not expected to have a material impact on Alliant Energy’s and IPL’s liquidity or collateral obligations. Alliant Energy’s, IPL’s and WPL’s current credit ratings and outlooks are as follows:

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 2025 Form 10-K and has not changed materially from the items reported in the 2025 Form 10-K, except for the items described in Notes 3, 6 and 12.

Quantitative and Qualitative Disclosures About Market Risk are reported in the 2025 Form 10-K and have not changed materially.

Alliant Energy’s, IPL’s and WPL’s management evaluated, with the participation of each of Alliant Energy’s, IPL’s and WPL’s Chief Executive Officer, Chief Financial Officer and Disclosure Committee, the effectiveness of the design and operation of Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934, as amended) as of March 31, 2026 pursuant to the requirements of the Securities Exchange Act of 1934, as amended. Based on their evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the quarter ended March 31, 2026.

There was no change in Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting that occurred during the quarter ended March 31, 2026 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting.