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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-Q
☒    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended March 31, 20212022

or

☐    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                    to                    

lnt-20220331_g1.jpg

Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number

ALLIANT ENERGY CORPORATION
(a Wisconsin Corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 1-9894
IRS Employer Identification Number - 39-1380265

INTERSTATE POWER & LIGHT COMPANY
(an Iowa corporation)
Alliant Energy Tower
Cedar Rapids, Iowa 52401
Telephone (319) 786-4411
Commission File Number - 1-4117
IRS Employer Identification Number - 42-0331370

WISCONSIN POWER & LIGHT COMPANY
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 0-337
IRS Employer Identification Number - 39-0714890
This combined Form 10-Q is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company. Information contained in the Form 10-Q relating to Interstate Power and Light Company and Wisconsin Power and Light Company is filed by each such registrant on its own behalf. Each of Interstate Power and Light Company and Wisconsin Power and Light Company makes no representation as to information relating to registrants other than itself.

Securities registered pursuant to Section 12(b) of the Act:
Alliant Energy Corporation, Common Stock, $0.01 Par Value, Trading Symbol LNT, Nasdaq Global Select Market
Interstate Power and Light Company, 5.100% Series D Cumulative Perpetual Preferred Stock, $0.01 Par Value, Trading Symbol IPLDP, Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Alliant Energy Corporation - Large Accelerated Filer ☒ Accelerated Filer ☐ Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐
Interstate Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐
Wisconsin Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Alliant Energy Corporation ☐
Interstate Power and Light Company ☐
Wisconsin Power and Light Company ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
Alliant Energy Corporation - Yes ☐ No ☒
Interstate Power and Light Company - Yes ☐ No ☒
Wisconsin Power and Light Company - Yes ☐ No ☒
Number of shares outstanding of each class of common stock as of March 31, 2021:2022:
Alliant Energy Corporation, Common Stock, $0.01 par value, 250,134,552250,813,728 shares outstanding
Interstate Power and Light Company, Common Stock, $2.50 par value, 13,370,788 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)
Wisconsin Power and Light Company, Common Stock, $5 par value, 13,236,601 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)



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DEFINITIONS
The following abbreviations or acronyms used in this report are defined below:
Abbreviation or AcronymDefinitionAbbreviation or AcronymDefinition
20202021 Form 10-KCombined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2020GAAPU.S. generally accepted accounting principles
AEFAlliant Energy Finance, LLC2021IPLInterstate Power and Light Company
Alliant EnergyAEFAlliant Energy CorporationFinance, LLCIUBIowa Utilities Board
ATCAFUDCAmerican Transmission Company LLCAllowance for funds used during constructionMDAManagement’s Discussion and Analysis of Financial Condition and Results of Operations
Alliant EnergyAlliant Energy CorporationMISOMidcontinent Independent System Operator, Inc.
ATCAmerican Transmission Company LLCMWMegawatt
ATC HoldingsInterest in American Transmission Company LLC and ATC Holdco LLCMISOMWhMidcontinent Independent System Operator, Inc.Megawatt-hour
Corporate ServicesAlliant Energy Corporate Services, Inc.MWN/AMegawatt
COVID-19Novel coronavirusMWhMegawatt-hourNot applicable
DAECDuane Arnold Energy CenterN/ANot applicable
DthDekathermNote(s)Combined Notes to Condensed Consolidated Financial Statements
DthDekathermOPEBOther postretirement benefits
EGUElectric generating unitOPEBPPAOther postretirement benefitsPurchased power agreement
EPAU.S. Environmental Protection AgencyPPAPSCWPurchased power agreementPublic Service Commission of Wisconsin
EPSEarnings per weighted average common sharePSCWSECPublic ServiceSecurities and Exchange Commission of Wisconsin
Federal Tax ReformFERCTax Cuts and Jobs ActFederal Energy Regulatory CommissionU.S.United States of America
FERCFinancial StatementsFederal Energy Regulatory CommissionCondensed Consolidated Financial StatementsWest RiversideWest Riverside Energy Center
Financial StatementsFTRCondensed Consolidated Financial Statementstransmission rightWhiting PetroleumWhiting Petroleum Corporation
FTRGAAPFinancial transmission rightU.S. generally accepted accounting principlesWPLWisconsin Power and Light Company

FORWARD-LOOKING STATEMENTS

Statements contained in this report that are not of historical fact are forward-looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified as such because the statements include words such as “may,” “believe,” “expect,” “anticipate,” “plan,” “project,” “will,” “projections,” “estimate,” or other words of similar import. Similarly, statements that describe future financial performance or plans or strategies are forward-looking statements. Such forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, such statements. Some, but not all, of the risks and uncertainties of Alliant Energy, IPL and WPL that could materially affect actual results include:

the direct or indirect effects resulting from the COVID-19 pandemic on sales volumes, margins, operations, employees, contractors, vendors, the ability to complete construction projects, supply chains, customers’ inability to pay bills, suspension of disconnects, the market value of the assets that fund pension plans and the potential for additional funding requirements, the ability of counterparties to meet their obligations, compliance with regulatory requirements, the ability to implement regulatory plans, economic conditions and access to capital markets;
the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;
the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber attacks, or responses to such incidents;
the impact of customer- and third party-owned generation, including alternative electric suppliers, in IPL’s and WPL’s service territories on system reliability, operating expenses and customers’ demand for electricity;
the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and margins;
the impact that price changes may have on IPL’s and WPL’s customers’ demand for electric, gas and steam services and their ability to pay their bills;
IPL’s and WPL’s ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel costs, operating costs, transmission costs, deferred expenditures, deferred tax assets, tax expense, capital expenditures, and remaining costs related to EGUs that may be permanently closed and certain other retired assets, decreases in sales volumes, earning their authorized rates of return, and the payments to their parent of expected levels of dividends;
federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;
the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;
the impacts of changes in the tax code, including tax rates, including minimum tax rates, and adjustments made to deferred tax assets and liabilities;
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Tablethe ability to complete construction of Contentsrenewable generation and storage projects by planned in-service dates and within the cost targets set by regulators due to cost increases of and access to materials, equipment and commodities including due to tariffs, duties or other assessments, such as any additional tariffs resulting from U.S. Department of Commerce investigations into the sourcing of solar project materials and equipment from certain countries, labor issues or supply shortages, the ability to successfully resolve warranty issues or contract disputes, the ability to achieve the expected level of tax benefits based on tax guidelines and project costs, and the ability to efficiently utilize the renewable generation and storage project tax benefits for the benefit of customers;
employee workforce factors, including changes in key executives, ability to hire and retain employees with specialized skills, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;
any material post-closing payments related to any past asset divestitures, including the sale of Whiting Petroleum, which could result from, among other things, indemnification agreements, warranties, guarantees or litigation;
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weather effects on results of utility operations;
the direct or indirect effects resulting from the ongoing novel coronavirus (COVID-19) pandemic and the spread of variant strains, including any vaccine mandates and testing requirements, on sales volumes, margins, operations, employees, labor markets, contractors, vendors, the ability to complete construction projects, supply chains, customers’ inability to pay bills, suspension of disconnects, the market value of the assets that fund pension plans and the potential for additional funding requirements, the ability of counterparties to meet their obligations, compliance with regulatory requirements, the ability to implement regulatory plans, economic conditions and access to capital markets;
issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions permits, the Coal Combustion Residuals Rule, future changes in environmental laws and regulations, including federal, state or local regulations for carbon dioxide emissions reductions from new and existing fossil-fueled EGUs, and litigation associated with environmental requirements;
increased pressure from customers, investors and other stakeholders to more rapidly reduce carbon dioxide emissions;
the ability to defend against environmental claims brought by state and federal agencies, such as the EPA, state natural resources agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;
inflation and interest rates;
disruptions to the supply of materials, equipment and commodities needed to construct solar generation and storage projects and maintain ongoing operations, including due to geopolitical issues, shortages, labor issues or transportation issues, which may, among other potential impacts, affect the ability to complete construction ofmeet capacity requirements and result in increased capacity expense;
possible changes to MISO’s methodology establishing capacity planning reserve margin and capacity accreditation requirements that may impact how and when new generating facilities such as IPL’s and WPL’s additional solar generation projects withinmay be accredited with energy capacity and may require IPL and WPL to adjust their current resource plans, the cost targets set by regulators andneed to add resources to comply with MISO’s proposal, or procure capacity in the ability to efficiently utilize the solar generation project tax benefits for the benefit of customers;market whereby such costs might not be recovered in rates;
changes in the price of delivered natural gas, transmission, purchased electricity and coal, and any resulting changes to counterparty credit risk, due to shifts in supply and demand caused by market conditions, regulations and regulations;MISO’s annual resource adequacy process;
disruptions in the supply and delivery of natural gas, purchased electricity and coal;
the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as mechanical problems and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;
issues related to the availability and operations of EGUs, including start-up risks, breakdown or failure of equipment, availability of warranty coverage for equipment breakdowns or failures, performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints, compliance with mandatory reliability standards and risks related to recovery of resulting incremental costs through rates;
impacts that excessive heat, excessive cold, storms or natural disasters may have on Alliant Energy’s, IPL’s and WPL’s operations and recovery of costs associated with restoration activities or on the operations of Alliant Energy’s investments;
Alliant Energy’s ability to sustain its dividend payout ratio goal;
changes to costs of providing benefits and related funding requirements of pension and OPEB plans due to the market value of the assets that fund the plans, economic conditions, financial market performance, interest rates, timing and form of benefits payments, life expectancies and demographics;
material changes in employee-related benefit and compensation costs;
risks associated with operation and ownership of non-utility holdings;
changes in technology that alter the channels through which customers buy or utilize Alliant Energy’s, IPL’s or WPL’s products and services;
impacts on equity income from unconsolidated investments from valuations and potential changes to ATC’s authorized return on equity;
impacts of IPL’s future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures, allocation of mixed service costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;
changes to the creditworthiness of counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;
current or future litigation, regulatory investigations, proceedings or inquiries;
reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal actions;
the effect of accounting standards issued periodically by standard-setting bodies;
the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows; and
other factors listed in MDA and Risk Factors in Item 1A in the 20202021 Form 10-K.

Alliant Energy, IPL and WPL each assume no obligation, and disclaim any duty, to update the forward-looking statements in this report, except as required by law.
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PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions, except per share amounts)(in millions, except per share amounts)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$701$730Electric utility$773$701
Gas utilityGas utility170152Gas utility262170
Other utilityOther utility1312Other utility1113
Non-utilityNon-utility1722Non-utility2217
Total revenuesTotal revenues901916Total revenues1,068901
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power133184Electric production fuel and purchased power168133
Electric transmission serviceElectric transmission service134122Electric transmission service138134
Cost of gas soldCost of gas sold10085Cost of gas sold168100
Other operation and maintenanceOther operation and maintenance146163Other operation and maintenance153146
Depreciation and amortizationDepreciation and amortization164146Depreciation and amortization166164
Taxes other than income taxesTaxes other than income taxes2628Taxes other than income taxes2726
Total operating expensesTotal operating expenses703728Total operating expenses820703
Operating incomeOperating income198188Operating income248198
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense6969Interest expense7469
Equity income from unconsolidated investments, netEquity income from unconsolidated investments, net(15)(13)Equity income from unconsolidated investments, net(15)(15)
Allowance for funds used during constructionAllowance for funds used during construction(4)(23)Allowance for funds used during construction(11)(4)
OtherOther21Other2
Total other (income) and deductionsTotal other (income) and deductions5234Total other (income) and deductions4852
Income before income taxesIncome before income taxes146154Income before income taxes200146
Income tax benefit(28)(19)
Income tax expense (benefit)Income tax expense (benefit)8(28)
Net incomeNet income174173Net income192174
Preferred dividend requirements of Interstate Power and Light CompanyPreferred dividend requirements of Interstate Power and Light Company33Preferred dividend requirements of Interstate Power and Light Company3
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners$171$170Net income attributable to Alliant Energy common shareowners$192$171
Weighted average number of common shares outstanding:Weighted average number of common shares outstanding:Weighted average number of common shares outstanding:
BasicBasic250.0244.4Basic250.6250.0
DilutedDiluted250.4244.6Diluted250.9250.4
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.68$0.70
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.77$0.68

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2021
December 31,
2020
March 31,
2022
December 31,
2021
(in millions, except per
share and share amounts)
(in millions, except per
share and share amounts)
ASSETSASSETSASSETS
Current assets:Current assets:Current assets:
Cash and cash equivalentsCash and cash equivalents$14$54Cash and cash equivalents$67$39
Accounts receivable, less allowance for expected credit lossesAccounts receivable, less allowance for expected credit losses325412Accounts receivable, less allowance for expected credit losses481440
Production fuel, at weighted average costProduction fuel, at weighted average cost5766Production fuel, at weighted average cost3951
Gas stored underground, at weighted average costGas stored underground, at weighted average cost2546Gas stored underground, at weighted average cost2782
Materials and supplies, at weighted average costMaterials and supplies, at weighted average cost122105Materials and supplies, at weighted average cost119113
Regulatory assetsRegulatory assets9581Regulatory assets88104
OtherOther117123Other271240
Total current assetsTotal current assets755887Total current assets1,0921,069
Property, plant and equipment, netProperty, plant and equipment, net14,35314,336Property, plant and equipment, net15,19214,987
Investments:Investments:Investments:
ATC HoldingsATC Holdings334331ATC Holdings346338
OtherOther160154Other187179
Total investmentsTotal investments494485Total investments533517
Other assets:Other assets:Other assets:
Regulatory assetsRegulatory assets1,9121,929Regulatory assets1,8311,836
Deferred charges and otherDeferred charges and other8073Deferred charges and other191144
Total other assetsTotal other assets1,9922,002Total other assets2,0221,980
Total assetsTotal assets$17,594$17,710Total assets$18,839$18,553
LIABILITIES AND EQUITYLIABILITIES AND EQUITYLIABILITIES AND EQUITY
Current liabilities:Current liabilities:Current liabilities:
Current maturities of long-term debtCurrent maturities of long-term debt$308$8Current maturities of long-term debt$333$633
Commercial paperCommercial paper336389Commercial paper276515
Accounts payableAccounts payable307377Accounts payable383436
Accrued taxesAccrued taxes6658
Regulatory liabilitiesRegulatory liabilities208249Regulatory liabilities251186
OtherOther249274Other212226
Total current liabilitiesTotal current liabilities1,4081,297Total current liabilities1,5212,054
Long-term debt, net (excluding current portion)Long-term debt, net (excluding current portion)6,4716,769Long-term debt, net (excluding current portion)7,3836,735
Other liabilities:Other liabilities:Other liabilities:
Deferred tax liabilitiesDeferred tax liabilities1,8431,814Deferred tax liabilities1,9581,927
Regulatory liabilitiesRegulatory liabilities1,0471,057Regulatory liabilities1,1211,085
Pension and other benefit obligationsPension and other benefit obligations495511Pension and other benefit obligations363374
OtherOther364374Other416388
Total other liabilitiesTotal other liabilities3,7493,756Total other liabilities3,8583,774
Commitments and contingencies (Note 12)
00
Commitments and contingencies (Note 12)
Commitments and contingencies (Note 12)
00
Equity:Equity:Equity:
Alliant Energy Corporation common equity:Alliant Energy Corporation common equity:Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 250,134,552 and 249,868,415 shares32
Common stock - $0.01 par value - 480,000,000 shares authorized; 250,813,728 and 250,474,529 shares outstandingCommon stock - $0.01 par value - 480,000,000 shares authorized; 250,813,728 and 250,474,529 shares outstanding33
Additional paid-in capitalAdditional paid-in capital2,7122,704Additional paid-in capital2,7502,749
Retained earningsRetained earnings3,0632,994Retained earnings3,3363,250
Accumulated other comprehensive loss(1)(1)
Shares in deferred compensation trust - 365,523 and 380,542 shares at a weighted average cost of $29.17 and $28.73 per share(11)(11)
Shares in deferred compensation trust - 381,397 and 383,532 shares at a weighted average cost of $31.17 and $30.59 per shareShares in deferred compensation trust - 381,397 and 383,532 shares at a weighted average cost of $31.17 and $30.59 per share(12)(12)
Total Alliant Energy Corporation common equityTotal Alliant Energy Corporation common equity5,7665,688Total Alliant Energy Corporation common equity6,0775,990
Cumulative preferred stock of Interstate Power and Light Company200200
Total equity5,9665,888
Total liabilities and equityTotal liabilities and equity$17,594$17,710Total liabilities and equity$18,839$18,553

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions)(in millions)
Cash flows from operating activities:Cash flows from operating activities:Cash flows from operating activities:
Net incomeNet income$174$173Net income$192$174
Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortizationDepreciation and amortization164146Depreciation and amortization166164
Deferred tax benefit and tax credits(29)(23)
Deferred tax expense (benefit) and tax creditsDeferred tax expense (benefit) and tax credits18(29)
OtherOther45Other(6)4
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(126)(119)Accounts receivable(161)(126)
Gas stored undergroundGas stored underground5520
Derivative assetsDerivative assets(85)6
Regulatory assetsRegulatory assets19(4)
Accounts payableAccounts payable(37)(6)
Regulatory liabilitiesRegulatory liabilities(60)(38)Regulatory liabilities92(60)
Deferred income taxesDeferred income taxes5850Deferred income taxes1558
Pension and other benefit obligations(16)(31)
OtherOther(24)(3)Other(17)(56)
Net cash flows from operating activitiesNet cash flows from operating activities145160Net cash flows from operating activities251145
Cash flows used for investing activities:Cash flows used for investing activities:Cash flows used for investing activities:
Construction and acquisition expenditures:Construction and acquisition expenditures:Construction and acquisition expenditures:
Utility businessUtility business(214)(278)Utility business(307)(214)
OtherOther(17)(11)Other(23)(17)
Cash receipts on sold receivablesCash receipts on sold receivables209123Cash receipts on sold receivables115209
OtherOther(16)(13)Other(8)(16)
Net cash flows used for investing activitiesNet cash flows used for investing activities(38)(179)Net cash flows used for investing activities(223)(38)
Cash flows from (used for) financing activities:Cash flows from (used for) financing activities:Cash flows from (used for) financing activities:
Common stock dividendsCommon stock dividends(102)(93)Common stock dividends(107)(102)
Proceeds from issuance of common stock, net8228
Proceeds from issuance of long-term debtProceeds from issuance of long-term debt0300Proceeds from issuance of long-term debt650
Payments to retire long-term debtPayments to retire long-term debt0(300)Payments to retire long-term debt(300)
Net change in commercial paper and other short-term borrowings(53)(67)
Net change in commercial paperNet change in commercial paper(239)(53)
OtherOther2(8)Other(1)10
Net cash flows from (used for) financing activitiesNet cash flows from (used for) financing activities(145)60Net cash flows from (used for) financing activities3(145)
Net increase (decrease) in cash, cash equivalents and restricted cashNet increase (decrease) in cash, cash equivalents and restricted cash(38)41Net increase (decrease) in cash, cash equivalents and restricted cash31(38)
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period5618Cash, cash equivalents and restricted cash at beginning of period4056
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$18$59Cash, cash equivalents and restricted cash at end of period$71$18
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash paid during the period for:Cash paid during the period for:Cash paid during the period for:
InterestInterest($59)($65)Interest($62)($59)
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$64$156Accrued capital expenditures$134$64
Beneficial interest obtained in exchange for securitized accounts receivableBeneficial interest obtained in exchange for securitized accounts receivable$107$188Beneficial interest obtained in exchange for securitized accounts receivable$227$107

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions)(in millions)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$386$425Electric utility$400$386
Gas utilityGas utility9183Gas utility13991
Steam and otherSteam and other1211Steam and other1112
Total revenuesTotal revenues489519Total revenues550489
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power59106Electric production fuel and purchased power6759
Electric transmission serviceElectric transmission service9284Electric transmission service9792
Cost of gas soldCost of gas sold5044Cost of gas sold8550
Other operation and maintenanceOther operation and maintenance7787Other operation and maintenance8377
Depreciation and amortizationDepreciation and amortization9486Depreciation and amortization9494
Taxes other than income taxesTaxes other than income taxes1415Taxes other than income taxes1414
Total operating expensesTotal operating expenses386422Total operating expenses440386
Operating incomeOperating income10397Operating income110103
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense3534Interest expense3735
Allowance for funds used during constructionAllowance for funds used during construction(2)(10)Allowance for funds used during construction(3)(2)
Other01
Total other (income) and deductionsTotal other (income) and deductions3325Total other (income) and deductions3433
Income before income taxesIncome before income taxes7072Income before income taxes7670
Income tax benefitIncome tax benefit(12)(14)Income tax benefit(11)(12)
Net incomeNet income8286Net income8782
Preferred dividend requirementsPreferred dividend requirements33Preferred dividend requirements3
Net income available for common stockNet income available for common stock$79$83Net income available for common stock$87$79
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2021
December 31,
2020
March 31,
2022
December 31,
2021
(in millions, except per
share and share amounts)
(in millions, except per
share and share amounts)
ASSETSASSETSASSETS
Current assets:Current assets:Current assets:
Cash and cash equivalentsCash and cash equivalents$11$50Cash and cash equivalents$62$34
Accounts receivable, less allowance for expected credit lossesAccounts receivable, less allowance for expected credit losses130210Accounts receivable, less allowance for expected credit losses257241
Income tax refunds receivableIncome tax refunds receivable258
Production fuel, at weighted average costProduction fuel, at weighted average cost4548Production fuel, at weighted average cost2829
Gas stored underground, at weighted average costGas stored underground, at weighted average cost820Gas stored underground, at weighted average cost1140
Materials and supplies, at weighted average costMaterials and supplies, at weighted average cost7363Materials and supplies, at weighted average cost7170
Regulatory assetsRegulatory assets7352Regulatory assets6073
OtherOther5353Other8569
Total current assetsTotal current assets393496Total current assets599564
Property, plant and equipment, netProperty, plant and equipment, net7,8727,889Property, plant and equipment, net7,9767,983
Other assets:Other assets:Other assets:
Regulatory assetsRegulatory assets1,4211,431Regulatory assets1,3721,370
Deferred charges and otherDeferred charges and other4033Deferred charges and other10379
Total other assetsTotal other assets1,4611,464Total other assets1,4751,449
Total assetsTotal assets$9,726$9,849Total assets$10,050$9,996
LIABILITIES AND EQUITYLIABILITIES AND EQUITYLIABILITIES AND EQUITY
Current liabilities:Current liabilities:Current liabilities:
Accounts payableAccounts payable$119$162Accounts payable$135$173
Accounts payable to associated companiesAccounts payable to associated companies045Accounts payable to associated companies4639
Regulatory liabilitiesRegulatory liabilities87103Regulatory liabilities12284
Accrued taxesAccrued taxes5756
Accrued interestAccrued interest3536
OtherOther131137Other6267
Total current liabilitiesTotal current liabilities337447Total current liabilities457455
Long-term debt, netLong-term debt, net3,3463,345Long-term debt, net3,6443,643
Other liabilities:Other liabilities:Other liabilities:
Deferred tax liabilitiesDeferred tax liabilities1,0471,035Deferred tax liabilities1,1071,083
Regulatory liabilitiesRegulatory liabilities574573Regulatory liabilities632607
Pension and other benefit obligationsPension and other benefit obligations180186Pension and other benefit obligations124127
OtherOther300299Other311312
Total other liabilitiesTotal other liabilities2,1012,093Total other liabilities2,1742,129
Commitments and contingencies (Note 12)
Commitments and contingencies (Note 12)
00
Commitments and contingencies (Note 12)
00
Equity:Equity:Equity:
Interstate Power and Light Company common equity:Interstate Power and Light Company common equity:Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstandingCommon stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding3333Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding3333
Additional paid-in capitalAdditional paid-in capital2,7522,752Additional paid-in capital2,8072,807
Retained earningsRetained earnings957979Retained earnings935929
Total Interstate Power and Light Company common equityTotal Interstate Power and Light Company common equity3,7423,764Total Interstate Power and Light Company common equity3,7753,769
Cumulative preferred stock200200
Total equity3,9423,964
Total liabilities and equityTotal liabilities and equity$9,726$9,849Total liabilities and equity$10,050$9,996

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions)(in millions)
Cash flows from (used for) operating activities:Cash flows from (used for) operating activities:Cash flows from (used for) operating activities:
Net incomeNet income$82$86Net income$87$82
Adjustments to reconcile net income to net cash flows from (used for) operating activities:Adjustments to reconcile net income to net cash flows from (used for) operating activities:Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortizationDepreciation and amortization9486Depreciation and amortization9494
Deferred tax expense (benefit) and tax creditsDeferred tax expense (benefit) and tax credits15(2)
OtherOther(3)(15)Other(2)(1)
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(133)(126)Accounts receivable(128)(133)
Income tax refunds receivableIncome tax refunds receivable(17)(3)
Gas stored undergroundGas stored underground2912
Derivative assetsDerivative assets(43)10
Regulatory assetsRegulatory assets(16)(9)Regulatory assets9(16)
Regulatory liabilitiesRegulatory liabilities(19)1Regulatory liabilities59(19)
Deferred income taxes1415
OtherOther(64)(13)Other(14)(69)
Net cash flows from (used for) operating activitiesNet cash flows from (used for) operating activities(45)25Net cash flows from (used for) operating activities89(45)
Cash flows from (used for) investing activities:
Cash flows from investing activities:Cash flows from investing activities:
Construction and acquisition expendituresConstruction and acquisition expenditures(106)(165)Construction and acquisition expenditures(96)(106)
Cash receipts on sold receivablesCash receipts on sold receivables209123Cash receipts on sold receivables115209
OtherOther(5)(11)Other(1)(5)
Net cash flows from (used for) investing activities98(53)
Cash flows from (used for) financing activities:
Net cash flows from investing activitiesNet cash flows from investing activities1898
Cash flows used for financing activities:Cash flows used for financing activities:
Common stock dividendsCommon stock dividends(101)(60)Common stock dividends(81)(101)
Capital contributions from parent0100
OtherOther94Other29
Net cash flows from (used for) financing activities(92)44
Net cash flows used for financing activitiesNet cash flows used for financing activities(79)(92)
Net increase (decrease) in cash, cash equivalents and restricted cashNet increase (decrease) in cash, cash equivalents and restricted cash(39)16Net increase (decrease) in cash, cash equivalents and restricted cash28(39)
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period509Cash, cash equivalents and restricted cash at beginning of period3450
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$11$25Cash, cash equivalents and restricted cash at end of period$62$11
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash (paid) refunded during the period for:Cash (paid) refunded during the period for:Cash (paid) refunded during the period for:
InterestInterest($37)($41)Interest($37)($37)
Income taxes, netIncome taxes, net$7$0Income taxes, net$—$7
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$31$92Accrued capital expenditures$27$31
Beneficial interest obtained in exchange for securitized accounts receivableBeneficial interest obtained in exchange for securitized accounts receivable$107$188Beneficial interest obtained in exchange for securitized accounts receivable$227$107

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions)(in millions)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$315$305Electric utility$373$315
Gas utilityGas utility7969Gas utility12379
OtherOther11Other1
Total revenuesTotal revenues395375Total revenues496395
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power7478Electric production fuel and purchased power10174
Electric transmission serviceElectric transmission service4238Electric transmission service4142
Cost of gas soldCost of gas sold5041Cost of gas sold8350
Other operation and maintenanceOther operation and maintenance5954Other operation and maintenance5859
Depreciation and amortizationDepreciation and amortization6959Depreciation and amortization7069
Taxes other than income taxesTaxes other than income taxes1111Taxes other than income taxes1211
Total operating expensesTotal operating expenses305281Total operating expenses365305
Operating incomeOperating income9094Operating income13190
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense2625Interest expense2726
Allowance for funds used during constructionAllowance for funds used during construction(2)(13)Allowance for funds used during construction(9)(2)
OtherOther10Other1
Total other (income) and deductionsTotal other (income) and deductions2512Total other (income) and deductions1825
Income before income taxesIncome before income taxes6582Income before income taxes11365
Income tax benefit(19)(8)
Income tax expense (benefit)Income tax expense (benefit)21(19)
Net incomeNet income$84$90Net income$92$84
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2021
December 31,
2020
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$2$3
Accounts receivable, less allowance for expected credit losses183192
Production fuel, at weighted average cost1218
Gas stored underground, at weighted average cost1726
Materials and supplies, at weighted average cost4740
Regulatory assets2229
Other4754
Total current assets330362
Property, plant and equipment, net6,0536,022
Other assets:
Regulatory assets491498
Deferred charges and other3630
Total other assets527528
Total assets$6,910$6,912
LIABILITIES AND EQUITY
Current liabilities:
Commercial paper$148$257
Accounts payable125154
Accounts payable to associated companies1735
Regulatory liabilities121146
Other9482
Total current liabilities505674
Long-term debt, net2,1312,130
Other liabilities:
Deferred tax liabilities719702
Regulatory liabilities473484
Finance lease obligations - Sheboygan Falls Energy Facility3942
Pension and other benefit obligations215222
Other183180
Total other liabilities1,6291,630
Commitments and contingencies (Note 12)
00
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding6666
Additional paid-in capital1,5841,459
Retained earnings995953
Total Wisconsin Power and Light Company common equity2,6452,478
Total liabilities and equity$6,910$6,912
March 31,
2022
December 31,
2021
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$4$2
Accounts receivable, less allowance for expected credit losses211188
Production fuel, at weighted average cost1123
Gas stored underground, at weighted average cost1642
Materials and supplies, at weighted average cost4541
Regulatory assets2831
Prepaid gross receipts tax3040
Other10286
Total current assets447453
Property, plant and equipment, net6,7476,538
Other assets:
Regulatory assets459466
Deferred charges and other9061
Total other assets549527
Total assets$7,743$7,518
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$250$250
Commercial paper157236
Accounts payable185190
Accounts payable to associated companies3439
Regulatory liabilities129102
Other10273
Total current liabilities857890
Long-term debt, net (excluding current portion)2,1802,179
Other liabilities:
Deferred tax liabilities759753
Regulatory liabilities489478
Pension and other benefit obligations154159
Other253236
Total other liabilities1,6551,626
Commitments and contingencies (Note 12)
00
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding6666
Additional paid-in capital1,8841,704
Retained earnings1,1011,053
Total Wisconsin Power and Light Company common equity3,0512,823
Total liabilities and equity$7,743$7,518

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2021202020222021
(in millions)(in millions)
Cash flows from operating activities:Cash flows from operating activities:Cash flows from operating activities:
Net incomeNet income$84$90Net income$92$84
Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortizationDepreciation and amortization6959Depreciation and amortization7069
Deferred tax benefit and tax creditsDeferred tax benefit and tax credits(28)(11)Deferred tax benefit and tax credits(2)(28)
OtherOther4(5)Other(3)4
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(23)9
Gas stored undergroundGas stored underground269
Derivative assetsDerivative assets(42)(4)
Accounts payableAccounts payable(24)(24)
Regulatory liabilitiesRegulatory liabilities(41)(39)Regulatory liabilities32(41)
Accrued taxesAccrued taxes218
Deferred income taxesDeferred income taxes4432Deferred income taxes844
OtherOther1622Other1218
Net cash flows from operating activitiesNet cash flows from operating activities148148Net cash flows from operating activities167148
Cash flows used for investing activities:Cash flows used for investing activities:Cash flows used for investing activities:
Construction and acquisition expendituresConstruction and acquisition expenditures(108)(113)Construction and acquisition expenditures(212)(108)
OtherOther(11)(11)Other(5)(11)
Net cash flows used for investing activitiesNet cash flows used for investing activities(119)(124)Net cash flows used for investing activities(217)(119)
Cash flows used for financing activities:
Cash flows from (used for) financing activities:Cash flows from (used for) financing activities:
Common stock dividendsCommon stock dividends(42)(43)Common stock dividends(44)(42)
Capital contributions from parentCapital contributions from parent12525Capital contributions from parent180125
Net change in commercial paper and other short-term borrowings(109)14
Net change in commercial paperNet change in commercial paper(79)(109)
OtherOther(4)(1)Other(5)(4)
Net cash flows used for financing activities(30)(5)
Net cash flows from (used for) financing activitiesNet cash flows from (used for) financing activities52(30)
Net increase (decrease) in cash, cash equivalents and restricted cashNet increase (decrease) in cash, cash equivalents and restricted cash(1)19Net increase (decrease) in cash, cash equivalents and restricted cash2(1)
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period34Cash, cash equivalents and restricted cash at beginning of period23
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$2$23Cash, cash equivalents and restricted cash at end of period$4$2
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash paid during the period for:Cash paid during the period for:Cash paid during the period for:
InterestInterest($21)($21)Interest($23)($21)
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$32$62Accrued capital expenditures$104$32

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
INTERSTATE POWER AND LIGHT COMPANY
WISCONSIN POWER AND LIGHT COMPANY

COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission.SEC. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on2021 Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 20212022 are not necessarily indicative of results that may be expected for the year ending December 31, 2021.2022.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash, Cash Equivalents and Restricted Cash - At March 31, 2022, Alliant Energy’s and IPL’s cash and cash equivalents included $59 million of money market fund investments, with an interest rate of 0.3%.

NOTE 2. REGULATORY MATTERS
Regulatory Assets and Regulatory Liabilities -
Regulatory assets were comprised of the following items (in millions):
Alliant EnergyIPLWPL
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
Tax-related$901$890$853$843$48$47
Pension and OPEB costs570580286291284289
Asset retirement obligations12011982813838
Assets retired early10811374773436
IPL’s DAEC PPA amendment108110108110
WPL’s Western Wisconsin gas distribution expansion investments55555555
Derivatives1326613713
Other13211785684749
$2,007$2,010$1,494$1,483$513$527

Other - In February 2021, portions of the central and southern U.S., including Alliant Energy’s service territories, experienced a prolonged period of very cold temperatures and a series of winter storms. These events created significant volatility and increases in commodity prices caused by higher demand for electricity and natural gas and disruptions in commodity supply, resulting in IPL under-recovering its natural gas costs. In March 2021, IPL received approval from the IUB to spread recovery of these higher natural gas costs from its retail customers through December 2021. As of March 31, 2021, IPL’s cumulative under-collection of these natural gas costs was $20 million, which is included in “Other” regulatory assets in the above table. The extreme temperatures in February 2021 did not impact WPL’s natural gas costs and IPL’s and WPL’s fuel-related costs to the extent of IPL’s natural gas costs.
Alliant EnergyIPLWPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Tax-related$949$934$896$884$53$50
Pension and OPEB costs453462224228229234
Asset retirement obligations13412894894039
Assets retired early889264662426
IPL’s DAEC PPA amendment84908490
WPL’s Western Wisconsin gas distribution expansion investments50525052
Commodity cost recovery4242224040
Other11914068845156
$1,919$1,940$1,432$1,443$487$497

Regulatory liabilities were comprised of the following items (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Tax-relatedTax-related$685$732$327$331$358$401Tax-related$578$585$310$312$268$273
Cost of removal obligationsCost of removal obligations371367242238129129Cost of removal obligations391384256252135132
DerivativesDerivatives2581661257713389
Electric transmission cost recoveryElectric transmission cost recovery676840392729Electric transmission cost recovery505129272124
WPL’s West Riverside liquidated damagesWPL’s West Riverside liquidated damages38383838WPL’s West Riverside liquidated damages35363536
Derivatives2628182583
OtherOther687334433430Other604934232626
$1,255$1,306$661$676$594$630$1,372$1,271$754$691$618$580

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Tax-related - Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities are primarily related to excess deferred tax benefits resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform. During the three months ended March 31, 2021, Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities decreased primarily due to returning a portion of these excess deferred tax benefits back to customers.

NOTE 3. RECEIVABLES
Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of March 31, 2021,2022, IPL had $15$109 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions):
2021202020222021
Maximum outstanding aggregate cash proceedsMaximum outstanding aggregate cash proceeds$100$96Maximum outstanding aggregate cash proceeds$36$100
Average outstanding aggregate cash proceedsAverage outstanding aggregate cash proceeds3024Average outstanding aggregate cash proceeds430

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
March 31, 2021December 31, 2020March 31, 2022December 31, 2021
Customer accounts receivableCustomer accounts receivable$124$114Customer accounts receivable$142$125
Unbilled utility revenuesUnbilled utility revenues7492Unbilled utility revenues96104
Receivables sold to third partyReceivables sold to third party198206Receivables sold to third party238229
Less: cash proceedsLess: cash proceeds751Less: cash proceeds11
Deferred proceedsDeferred proceeds123205Deferred proceeds237228
Less: allowance for expected credit lossesLess: allowance for expected credit losses1617Less: allowance for expected credit losses1014
Fair value of deferred proceedsFair value of deferred proceeds$107$188Fair value of deferred proceeds$227$214

As of March 31, 2021,2022, outstanding receivables past due under the Receivables Agreement were $22$24 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions):
20212020
Collections$529$541
Write-offs, net of recoveries22

In April 2021, IPL amended and extended through March 2023 the purchase commitment from the third party to which it sells its receivables. Effective April 2021, the limit on cash proceeds is $110 million.
20222021
Collections$561$529
Write-offs, net of recoveries22

NOTE 4. INVESTMENTS
Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions):
2021202020222021
ATC HoldingsATC Holdings($11)($11)ATC Holdings($11)($11)
OtherOther(4)(2)Other(4)(4)
($15)($13)($15)($15)

NOTE 5. COMMON EQUITY
Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 20212022249,868,415250,474,529 
Shareowner Direct Plan152,588116,431 
Equity-based compensation plans113,549222,768 
Shares outstanding, March 31, 20212022250,134,552250,813,728 

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Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant EnergyAlliant EnergyTotal Alliant Energy Common EquityAlliant EnergyTotal Alliant Energy Common Equity
AccumulatedShares inCumulativeAccumulatedShares inCumulative
AdditionalOtherDeferredPreferredAdditionalOtherDeferredPreferred
CommonPaid-InRetainedComprehensiveCompensationStockTotalCommonPaid-InRetainedComprehensiveCompensationStockTotal
StockCapitalEarningsIncome (Loss)Trustof IPLEquityStockCapitalEarningsLossTrustof IPLEquity
Three Months Ended March 31, 2022Three Months Ended March 31, 2022
Beginning balance, December 31, 2021Beginning balance, December 31, 2021$3$2,749$3,250$—($12)$—$5,990
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners192192
Common stock dividends ($0.4275 per share)Common stock dividends ($0.4275 per share)(107)(107)
Shareowner Direct Plan issuancesShareowner Direct Plan issuances77
Equity-based compensation plans and otherEquity-based compensation plans and other(6)1(5)
Ending balance, March 31, 2022Ending balance, March 31, 2022$3$2,750$3,336$—($12)$—$6,077
Three Months Ended March 31, 2021Three Months Ended March 31, 2021Three Months Ended March 31, 2021
Beginning balance, December 31, 2020Beginning balance, December 31, 2020$2$2,704$2,994($1)($11)$200$5,888Beginning balance, December 31, 2020$2$2,704$2,994($1)($11)$200$5,888
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners171171Net income attributable to Alliant Energy common shareowners171171
Common stock dividends ($0.4025 per share)Common stock dividends ($0.4025 per share)(102)(102)Common stock dividends ($0.4025 per share)(102)(102)
Shareowner Direct Plan issuancesShareowner Direct Plan issuances178Shareowner Direct Plan issuances178
Equity-based compensation plans and otherEquity-based compensation plans and other101Equity-based compensation plans and other11
Ending balance, March 31, 2021Ending balance, March 31, 2021$3$2,712$3,063($1)($11)$200$5,966Ending balance, March 31, 2021$3$2,712$3,063($1)($11)$200$5,966
Three Months Ended March 31, 2020
Beginning balance, December 31, 2019$2$2,446$2,766$1($10)$200$5,405
Net income attributable to Alliant Energy common shareowners170170
Common stock dividends ($0.38 per share)(93)(93)
Equity forward settlements and Shareowner Direct Plan issuances0228228
Adoption of new accounting standard, net of tax(9)(9)
Other comprehensive income, net of tax11
Ending balance, March 31, 2020$2$2,674$2,834$2($10)$200$5,702
IPLIPLTotal IPL Common EquityIPLTotal IPL Common Equity
AdditionalCumulativeAdditionalCumulative
CommonPaid-InRetainedPreferredTotalCommonPaid-InRetainedPreferredTotal
StockCapitalEarningsStockEquityStockCapitalEarningsStockEquity
Three Months Ended March 31, 2022Three Months Ended March 31, 2022
Beginning balance, December 31, 2021Beginning balance, December 31, 2021$33$2,807$929$—$3,769
Net income available for common stockNet income available for common stock8787
Common stock dividendsCommon stock dividends(81)(81)
Ending balance, March 31, 2022Ending balance, March 31, 2022$33$2,807$935$—$3,775
Three Months Ended March 31, 2021Three Months Ended March 31, 2021Three Months Ended March 31, 2021
Beginning balance, December 31, 2020Beginning balance, December 31, 2020$33$2,752$979$200$3,964Beginning balance, December 31, 2020$33$2,752$979$200$3,964
Net income available for common stockNet income available for common stock7979Net income available for common stock7979
Common stock dividendsCommon stock dividends(101)(101)Common stock dividends(101)(101)
Ending balance, March 31, 2021Ending balance, March 31, 2021$33$2,752$957$200$3,942Ending balance, March 31, 2021$33$2,752$957$200$3,942
Three Months Ended March 31, 2020
Beginning balance, December 31, 2019$33$2,348$891$200$3,472
Net income available for common stock8383
Common stock dividends(60)(60)
Capital contributions from parent100100
Ending balance, March 31, 2020$33$2,448$914$200$3,595
WPLWPLAdditionalTotalWPLAdditionalTotal
CommonPaid-InRetainedCommonCommonPaid-InRetainedCommon
StockCapitalEarningsEquityStockCapitalEarningsEquity
Three Months Ended March 31, 2022Three Months Ended March 31, 2022
Beginning balance, December 31, 2021Beginning balance, December 31, 2021$66$1,704$1,053$2,823
Net incomeNet income9292
Common stock dividendsCommon stock dividends(44)(44)
Capital contributions from parentCapital contributions from parent180180
Ending balance, March 31, 2022Ending balance, March 31, 2022$66$1,884$1,101$3,051
Three Months Ended March 31, 2021Three Months Ended March 31, 2021Three Months Ended March 31, 2021
Beginning balance, December 31, 2020Beginning balance, December 31, 2020$66$1,459$953$2,478Beginning balance, December 31, 2020$66$1,459$953$2,478
Net incomeNet income8484Net income8484
Common stock dividendsCommon stock dividends(42)(42)Common stock dividends(42)(42)
Capital contributions from parentCapital contributions from parent125125Capital contributions from parent125125
Ending balance, March 31, 2021Ending balance, March 31, 2021$66$1,584$995$2,645Ending balance, March 31, 2021$66$1,584$995$2,645
Three Months Ended March 31, 2020
Beginning balance, December 31, 2019$66$1,434$864$2,364
Net income9090
Common stock dividends(43)(43)
Capital contributions from parent2525
Ending balance, March 31, 2020$66$1,459$911$2,436

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NOTE 6. DEBT
NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
March 31, 2021Alliant EnergyIPLWPL
March 31, 2022March 31, 2022Alliant EnergyIPLWPL
Amount outstandingAmount outstanding$336$0$148Amount outstanding$276$—$157
Weighted average interest ratesWeighted average interest rates0.2%N/A0.1%Weighted average interest rates0.6%N/A0.5%
Available credit facility capacityAvailable credit facility capacity$664$250$152Available credit facility capacity$724$250$143
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Three Months Ended March 31Three Months Ended March 31202120202021202020212020Three Months Ended March 31202220212022202120222021
Maximum amount outstanding (based on daily outstanding balances)Maximum amount outstanding (based on daily outstanding balances)$578$463$0$1$275$212Maximum amount outstanding (based on daily outstanding balances)$577$578$—$—$252$275
Average amount outstanding (based on daily outstanding balances)Average amount outstanding (based on daily outstanding balances)$424$382$0$0$189$167Average amount outstanding (based on daily outstanding balances)$443$424$—$—$205$189
Weighted average interest ratesWeighted average interest rates0.2%1.8%0%1.8%0.2%1.8%Weighted average interest rates0.3%0.2%—%—%0.3%0.2%

NOTE 6(b) Long-term Debt - In February 2022, AEF issued $350 million of 3.6% senior notes due 2032. The net proceeds from the issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In March 2022, AEF entered into a $300 million variable rate (1% as of March 31, 2022) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2024, and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that expired in March 2022.

NOTE 7. REVENUES
Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Three Months Ended March 31Three Months Ended March 31202120202021202020212020Three Months Ended March 31202220212022202120222021
Electric Utility:Electric Utility:Electric Utility:
Retail - residentialRetail - residential$262$266$139$147$123$119Retail - residential$293$262$150$139$143$123
Retail - commercialRetail - commercial1721831101206263Retail - commercial1881721181107062
Retail - industrialRetail - industrial2022101121219089Retail - industrial21120211111210090
WholesaleWholesale404011142926Wholesale474015113229
Bulk power and otherBulk power and other25311423118Bulk power and other34256142811
Total Electric UtilityTotal Electric Utility701730386425315305Total Electric Utility773701400386373315
Gas Utility:Gas Utility:Gas Utility:
Retail - residentialRetail - residential999152494742Retail - residential1589985527347
Retail - commercialRetail - commercial534527242621Retail - commercial825340274226
Retail - industrialRetail - industrial543222Retail - industrial855332
Transportation/otherTransportation/other13129844Transportation/other14139954
Total Gas UtilityTotal Gas Utility17015291837969Total Gas Utility2621701399112379
Other Utility:Other Utility:Other Utility:
SteamSteam910910Steam9999
Other utilityOther utility423111Other utility24231
Total Other UtilityTotal Other Utility1312121111Total Other Utility111311121
Non-Utility and Other:Non-Utility and Other:Non-Utility and Other:
Transportation and other1722
Travero and otherTravero and other2217
Total Non-Utility and OtherTotal Non-Utility and Other1722Total Non-Utility and Other2217
Total revenuesTotal revenues$901$916$489$519$395$375Total revenues$1,068$901$550$489$496$395
NOTE 8. INCOME TAXES
Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreasesincreases in Alliant Energy’s and WPL’s overall effective income tax rates for the three months ended March 31, 20212022 compared to the same period in 20202021 were primarily due to increaseddecreased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2021 increased revenue requirements.WPL.
Alliant EnergyIPLWPL
Three Months Ended March 31202120202021202020212020
Overall income tax rate(19%)(12%)(17%)(19%)(29%)(10%)
Alliant EnergyIPLWPL
202220212022202120222021
Overall income tax rate4%(19%)(14%)(17%)19%(29%)

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Deferred Tax Assets and Liabilities -
Carryforwards - At March 31, 2021,2022, carryforwards and expiration dates were estimated as follows (in millions):
Range of Expiration DatesAlliant EnergyIPLWPLRange of Expiration DatesAlliant EnergyIPLWPL
Federal net operating lossesFederal net operating losses2037$331$306$3Federal net operating losses2037$94$87$1
State net operating lossesState net operating losses2021-2041627162State net operating losses2022-2042578132
Federal tax creditsFederal tax credits2022-2041481280180Federal tax credits2022-2042589369197

Iowa Tax Reform - In March 2022, Iowa tax reform was enacted, which would reduce the current 9.8% Iowa corporate income tax rate beginning in 2023 if certain state income tax revenue triggers are satisfied. Annually, and by each November 1, the Iowa Department of Revenue will establish corporate income tax rates for the next tax year based on net corporate income tax receipts for the prior tax year. Rate reductions are currently expected to occur over a period of several years, with a target corporate income tax rate of 5.5%. Alliant Energy is currently unable to predict with certainty the timing or amount of any rate reductions. The majority of any reduction in income tax expense as a result of the lower Iowa corporate income tax rate is currently expected to reduce rates for IPL’s customers. In addition, after the 2023 corporate income tax rate is known in the fourth quarter of 2022, Alliant Energy currently expects to record a charge related to the remeasurement of accumulated deferred income tax assets at its non-utility businesses.

NOTE 9. BENEFIT PLANS
NOTE 9(a) Pension and OPEB Plans -
Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included below (in millions). For IPL and WPL, amounts are for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.
Defined Benefit Pension PlansOPEB PlansDefined Benefit Pension PlansOPEB Plans
Alliant EnergyAlliant Energy2021202020212020Alliant Energy2022202120222021
Service costService cost$3$3$1$1Service cost$2$3$1$1
Interest costInterest cost81112Interest cost9811
Expected return on plan assetsExpected return on plan assets(17)(18)(1)(2)Expected return on plan assets(17)(17)(1)(1)
Amortization of actuarial lossAmortization of actuarial loss10911Amortization of actuarial loss81011
Settlement losses (a)0400
$4$9$2$2
$2$4$2$2
Defined Benefit Pension PlansOPEB PlansDefined Benefit Pension PlansOPEB Plans
IPLIPL2021202020212020IPL2022202120222021
Service costService cost$2$1$0$0Service cost$2$2$—$—
Interest costInterest cost4511Interest cost4411
Expected return on plan assetsExpected return on plan assets(8)(8)(1)(1)Expected return on plan assets(8)(8)(1)(1)
Amortization of actuarial lossAmortization of actuarial loss4400Amortization of actuarial loss34
$2$2$0$0$1$2$—$—
Defined Benefit Pension PlansOPEB Plans
WPL2021202020212020
Service cost$1$1$0$0
Interest cost4501
Expected return on plan assets(8)(8)00
Amortization of actuarial loss5410
$2$2$1$1

(a)Settlement losses related to payments made to retired executives of Alliant Energy.
Defined Benefit Pension PlansOPEB Plans
WPL2022202120222021
Service cost$1$1$—$—
Interest cost441
Expected return on plan assets(8)(8)
Amortization of actuarial loss451
$1$2$1$1

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
202120202021202020212020202220212022202120222021
Compensation expenseCompensation expense$3 $3 $1 $1 $1 $1 Compensation expense$4$3$2$1$2$1
Income tax benefitsIncome tax benefits1 0 0 Income tax benefits111

As of March 31, 2021,2022, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $13$15 million, $7$8 million and $5$6 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

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For the three months ended March 31, 2021,2022, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards.
Weighted AverageWeighted Average
GrantsGrant Date Fair ValueGrantsGrant Date Fair Value
Performance sharesPerformance shares72,774$46.19Performance shares70,240$54.45
Performance restricted stock unitsPerformance restricted stock units72,77448.61Performance restricted stock units80,25256.62
Restricted stock unitsRestricted stock units79,86248.61Restricted stock units74,36056.62

As of March 31, 2021, 425,8492022, 322,288 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

NOTE 10. DERIVATIVE INSTRUMENTS
Commodity Derivatives -
Notional Amounts - As of March 31, 2021,2022, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):
FTRsNatural GasCoalDiesel FuelFTRsNatural GasCoalDiesel Fuel
MWhsYearsDthsYearsTonsYearsGallonsYearsMWhsYearsDthsYearsTonsYearsGallonsYears
Alliant EnergyAlliant Energy3,531 2021198,347 2021-20285,601 2021-20234,914 2021-2022Alliant Energy3,304 2022175,658 2022-20302,653 2022-20232,268 2022
IPLIPL1,203 202197,747 2021-20282,100 2021-2023IPL784 202294,175 2022-20301,053 2022-2023— 
WPLWPL2,328 2021100,600 2021-20273,501 2021-20234,914 2021-2022WPL2,520 202281,483 2022-20301,600 2022-20232,268 2022

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
March 31,
2021
December 31,
2020
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Current derivative assetsCurrent derivative assets$18$24$12$20$6$4Current derivative assets$151$113$68$48$83$65
Non-current derivative assetsNon-current derivative assets10107931Non-current derivative assets1106359365127
Current derivative liabilitiesCurrent derivative liabilities290326Current derivative liabilities683434
Non-current derivative liabilitiesNon-current derivative liabilities11166957Non-current derivative liabilities1111

During the three months ended March 31, 2022, Alliant Energy’s, IPL’s and WPL’s derivative assets increased primarily as a result of higher natural gas prices. Based on IPL’s and WPL’s natural gas cost recovery mechanisms, this resulted in corresponding increases in derivative regulatory liabilities on the balance sheets.

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At March 31, 20212022 and December 31, 2020,2021, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at March 31, 20212022 and December 31, 2020.2021. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

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NOTE 11. FAIR VALUE MEASUREMENTS
Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):
Alliant EnergyAlliant EnergyMarch 31, 2021December 31, 2020Alliant EnergyMarch 31, 2022December 31, 2021
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
Money market fund investmentsMoney market fund investments$8 $8 $0 $0 $8 $44 $44 $0 $0 $44 Money market fund investments$59 $59 $— $— $59 $32 $32 $— $— $32 
DerivativesDerivatives28 0 12 16 28 34 29 34 Derivatives261  251 10 261 176 — 146 30 176 
Deferred proceedsDeferred proceeds107 0 0 107 107 188 188 188 Deferred proceeds227   227 227 214 — — 214 214 
Liabilities:Liabilities:Liabilities:
DerivativesDerivatives13 0 13 0 13 25 25 25 Derivatives7  7  7 — 
Long-term debt (incl. current maturities)Long-term debt (incl. current maturities)6,779 0 7,613 1 7,614 6,777 8,107 8,109 Long-term debt (incl. current maturities)7,716  7,971 1 7,972 7,368 — 8,329 8,330 
IPLIPLMarch 31, 2021December 31, 2020IPLMarch 31, 2022December 31, 2021
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
Money market fund investmentsMoney market fund investments$8 $8 $0 $0 $8 $44 $44 $0 $0 $44 Money market fund investments$59 $59 $— $— $59 $32 $32 $— $— $32 
DerivativesDerivatives19 0 4 15 19 29 26 29 Derivatives127  120 7 127 84 — 65 19 84 
Deferred proceedsDeferred proceeds107 0 0 107 107 188 188 188 Deferred proceeds227   227 227 214 — — 214 214 
Liabilities:Liabilities:Liabilities:
DerivativesDerivatives6 0 6 0 6 12 12 12 Derivatives4  4  4 — 
Long-term debtLong-term debt3,346 0 3,745 0 3,745 3,345 4,021 4,021 Long-term debt3,644  3,738  3,738 3,643 — 4,124 — 4,124 
WPLWPLMarch 31, 2021December 31, 2020WPLMarch 31, 2022December 31, 2021
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
DerivativesDerivatives$9 $0 $8 $1 $9 $5 $0 $2 $3 $5 Derivatives$134 $— $131 $3 $134 $92 $— $81 $11 $92 
Liabilities:Liabilities:Liabilities:
DerivativesDerivatives7 0 7 0 7 13 13 13 Derivatives3  3  3 — — 
Long-term debt2,131 0 2,495 0 2,495 2,130 2,690 2,690 
Long-term debt (incl. current maturities)Long-term debt (incl. current maturities)2,430  2,592  2,592 2,429 — 2,862 — 2,862 

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.:
Alliant EnergyAlliant EnergyCommodity Contract DerivativeAlliant EnergyCommodity Contract Derivative
Assets and (Liabilities), netDeferred ProceedsAssets and (Liabilities), netDeferred Proceeds
Three Months Ended March 31Three Months Ended March 312021202020212020Three Months Ended March 312022202120222021
Beginning balance, January 1Beginning balance, January 1$29$21$188$188Beginning balance, January 1$29$29$214$188
Total net losses included in changes in net assets (realized/unrealized)Total net losses included in changes in net assets (realized/unrealized)(6)(3)00Total net losses included in changes in net assets (realized/unrealized)(6)(6)
Settlements (a)Settlements (a)(7)(4)(81)0Settlements (a)(13)(7)13(81)
Ending balance, March 31Ending balance, March 31$16$14$107$188Ending balance, March 31$10$16$227$107
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31($6)($3)$0$0
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($5)($6)$—$—
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IPLCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Three Months Ended March 312022202120222021
Beginning balance, January 1$18$26$214$188
Total net losses included in changes in net assets (realized/unrealized)(4)(5)
Settlements (a)(7)(6)13(81)
Ending balance, March 31$7$15$227$107
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($4)($6)$—$—
WPLCommodity Contract Derivative
Assets and (Liabilities), net
Three Months Ended March 3120222021
Beginning balance, January 1$11$3
Total net losses included in changes in net assets (realized/unrealized)(2)(1)
Settlements(6)(1)
Ending balance, March 31$3$1
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($1)$—
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IPLCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Three Months Ended March 312021202020212020
Beginning balance, January 1$26$18$188$188
Total net losses included in changes in net assets (realized/unrealized)(5)(2)00
Settlements (a)(6)(3)(81)0
Ending balance, March 31$15$13$107$188
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31($6)($2)$0$0
(a)Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for expected credit losses associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):
Alliant EnergyIPLWPL
Excluding FTRsFTRsExcluding FTRsFTRsExcluding FTRsFTRs
March 31, 2021$11$5$11$4$0$1
December 31, 2020181117912
Alliant EnergyIPLWPL
Excluding FTRsFTRsExcluding FTRsFTRsExcluding FTRsFTRs
March 31, 2022$3$7$3$4$—$3
December 31, 2021920810110

NOTE 12. COMMITMENTS AND CONTINGENCIES
NOTE 12(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects, including WPL’s expansion of solar generation. At March 31, 2021,2022, Alliant Energy’s and WPL’s minimum future commitments for these projects were $10$214 million and $10$213 million, respectively.

NOTE 12(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At March 31, 2021,2022, related minimum future commitments were as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Natural gasNatural gas$958$466$492Natural gas$939$472$467
CoalCoal945539Coal1277255
Other (a)Other (a)1226030Other (a)1356636
$1,174$581$561$1,201$610$558

(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2021.2022.

NOTE 12(c) Guarantees and Indemnifications -
Whiting Petroleum - - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. The guarantees do not include a maximum limit. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships, and currently known obligations include costs associated with the future abandonment of certain facilities owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC may need to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.
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As of March 31, 2021,2022, the currently known partnership obligations for the abandonment obligations are estimated at $68$60 million, which represents Alliant Energy’s currently estimated maximum exposure under the guarantees. Alliant Energy estimates its expected loss to be a portion of the $68$60 million of known partnership abandonment obligations of the Whiting Petroleum affiliate and the other partners. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, as of both March 31, 20212022 and December 31, 2020,2021, a liability of $5 million is recorded in “Other liabilities” on Alliant Energy’s balance sheets for expected credit losses related to the contingent obligations that are in the scope of these guarantees.

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Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $74$67 million as of March 31, 20212022 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of March 31, 20212022 and December 31, 2020.2021.

NOTE 12(d) Environmental Matters -
Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At March 31, 2021,2022, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At March 31, 2021,2022, such amounts for WPL were not material.
Alliant EnergyIPLAlliant EnergyIPL
Range of estimated future costsRange of estimated future costs$9 -$25$7 -$19Range of estimated future costs$10 -$26$7 -$20
Current and non-current environmental liabilitiesCurrent and non-current environmental liabilities$13$9Current and non-current environmental liabilities$12$9

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 12(e) Collective Bargaining Agreements - At March 31, 2022, employees covered by collective bargaining agreements represented 55%, 70% and 83% of total employees of Alliant Energy, IPL and WPL, respectively. In May 2022, WPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 965 expires, representing 26% and 83% of total employees of Alliant Energy and WPL, respectively. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and WPL are currently unable to predict the outcome.

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NOTE 13. SEGMENTS OF BUSINESS
Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.
Alliant EnergyATC Holdings,Alliant
UtilityNon-Utility,Energy
ElectricGasOtherTotalParent and OtherConsolidated
(in millions)
Three Months Ended March 31, 2021
Revenues$701$170$13$884$17$901
Operating income1474421935198
Net income attributable to Alliant Energy common shareowners1638171
Three Months Ended March 31, 2020
Revenues$730$152$12$894$22$916
Operating income (loss)146414191(3)188
Net income (loss) attributable to Alliant Energy common shareowners173(3)170
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Alliant EnergyATC Holdings,Alliant
UtilityNon-Utility,Energy
ElectricGasOtherTotalParent and OtherConsolidated
(in millions)
Three Months Ended March 31, 2022
Revenues$773$262$11$1,046$22$1,068
Operating income1815732417248
Net income attributable to Alliant Energy common shareowners17913192
Three Months Ended March 31, 2021
Revenues$701$170$13$884$17$901
Operating income1474421935198
Net income attributable to Alliant Energy common shareowners1638171
IPLElectricGasOtherTotal
(in millions)
Three Months Ended March 31, 2021
Revenues$386$91$12$489
Operating income72301103
Net income available for common stock79
Three Months Ended March 31, 2020
Revenues$425$83$11$519
Operating income6727397
Net income available for common stock83
WPLElectricGasOtherTotal
IPLIPLElectricGasOtherTotal
(in millions)(in millions)
Three Months Ended March 31, 2022Three Months Ended March 31, 2022
RevenuesRevenues$400$139$11$550
Operating incomeOperating income75323110
Net income available for common stockNet income available for common stock87
Three Months Ended March 31, 2021Three Months Ended March 31, 2021Three Months Ended March 31, 2021
RevenuesRevenues$315$79$1$395Revenues$386$91$12$489
Operating incomeOperating income7514190Operating income72301103
Net income84
Three Months Ended March 31, 2020
Revenues$305$69$1$375
Operating income7914194
Net income90
Net income available for common stockNet income available for common stock79
WPLElectricGasOtherTotal
(in millions)
Three Months Ended March 31, 2022
Revenues$373$123$—$496
Operating income10625131
Net income92
Three Months Ended March 31, 2021
Revenues$315$79$1$395
Operating income7514190
Net income84

NOTE 14. RELATED PARTIES
Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions):
IPLWPLIPLWPL
20212020202120202022202120222021
Corporate Services billingsCorporate Services billings$40$37$35$32Corporate Services billings$40$40$36$35
Sales creditedSales credited11512Sales credited1181
Purchases billedPurchases billed143812620Purchases billed941432226

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Net intercompany payables to Corporate Services were as follows (in millions):
IPLWPL
March 31, 2021December 31, 2020March 31, 2021December 31, 2020
Net payables to Corporate Services$73$110$60$73
IPLWPL
March 31, 2022December 31, 2021March 31, 2022December 31, 2021
Net payables to Corporate Services$120$110$76$83

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):
20212020
ATC billings to WPL$32$28
WPL billings to ATC33

20222021
ATC billings to WPL$34$32
WPL billings to ATC33

WPL owed ATC net amounts of $9 million as of March 31, 20212022 and $9$10 million as of December 31, 2020.2021.

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 20202021 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

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20212022 HIGHLIGHTS

Key highlights since the filing of the 20202021 Form 10-K include the following:

Customer Investments:
In response to a petition from a U.S.-based solar panel assembler, in March 2022, the U.S. Department of Commerce initiated an investigation into whether the sourcing of solar project materials and equipment from certain Southeast Asian countries circumvent tariffs and duties imposed on such materials and equipment imported from China. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters; however, this could result in delays and/or higher costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, and impact Alliant Energy’s, IPL’s and WPL’s anticipated future construction and acquisition expenditures.
In April 2022, the IUB issued an order approving IPL’s request for an extension of the procedural schedule related to its November 2021 advance rate-making principles filing with the IUB for up to 400 MW of new solar generation and 75 MW of battery storage. IPL requested an extension in order to review the proposed fixed cost cap included in its November 2021 filing given the cost pressures prevalent in the solar generation and battery storage markets, as well as narrow the selection of certain solar generation projects included in the filing. IPL currently expects a decision on its advance rate-making principles filing by the end of 2022.
In April 2022, WPL filed a Certificate of Authority withreceived an oral decision from the PSCW for approvalits second certificate of authority authorizing WPL to acquire, construct, own, and operate up to 414 MW of new solar generation by the end of 2023 in the following Wisconsin counties: Dodge (150 MW), Waushara (99 MW), Rock (65 MW), Grant (50 MW) and Green (50 MW). In April 2021, WPL received an oral decision from the PSCW authorizing WPL to acquire, own and operate 675 MW of new solar generation in various Wisconsin counties, and a written order from the PSCW is currently expected in May 2021. A significant majority of the capital expenditures for these 1,089 MWs of solar generation projects were included in the anticipated construction and acquisition expenditures included in “Liquidity and Capital Resources” in the 2020 Form 10-K. WPL proposes to own and operate the solar generation projects, which are currently expected to qualify for 30% investment tax credits, through a tax equity partnership, with approximately 35% to 45% of the construction costs financed with capital from the tax equity partner. WPL requested to include $355 million and $585 million in rate base for the 414 MW and 675 MW of new solar generation, respectively, which reflects its portion of capital expenditures, less the amounts financed by the tax equity partner. The 1,089 MW of new solar generation would replace energy and capacity being eliminated with the planned retirement of the coal-fired Edgewater Generating Station (414 MW) by the end of 2022, and Columbia Unit 1 by the end of 2023 and Columbia Unit 2 by the end of 2024 (595 MW in aggregate).

Rate Matters:
In May 2021, WPL filed a notice with the PSCW of its intent to enter into a settlement agreement with certain intervenor groups for annual base rate increases of $70 million and $15 million for WPL’s retail electric and gas customers, respectively, covering the 2022/2023 forward looking Test Period. The key drivers for the proposed annual base rate increases include lower excess deferred income tax benefits in 2022 and 2023 and revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation. In addition, tentative agreement has been reached proposing WPL maintain its current authorized return on common equity of 10%, implement a 54% common equity component of regulatory capital structure, as well as receive a recovery of and a return on the remaining net book value of Edgewater Unit 5, which is currently expected to be retired by the end of 2022. WPL currently plans to file its related rate review request with the PSCW in the second quarter of 2021 and expects any rate changes granted from this request to be effective on January 1, 2022 and extend through the end of 2023.
In April 2021, the IUB issued an order that new rules are to be adopted, which would establish minimum filing requirements for rate reviews using a forward-looking test period, and the related subsequent proceeding review after the close of the forward-looking test period. The rules provide that in the subsequent proceeding review, a utility’s actual costs and revenues shall be presumed to be reasonably consistent with the forward-looking test period if the utility’s actual return on common equity falls with a standard of reasonableness of 50 basis points above or 50 basis points below the authorized return on common equity. The new rules are currently expected to be effective later in 2021.

Legislative Matters:
In March 2021, the American Rescue Plan ActRefer to Note 8 for discussion of 2021 (Act) was enacted. The most significant provision of the Act for Alliant Energy is reduced minimum pension plan funding requirements, which Alliant Energy is currently evaluating. The Act also provides additional funding to the Low Income Home Energy Assistance Program, which assists certain of Alliant Energy’s customers with managing their energy costs, as well as provides financial support for certain of Alliant Energy’s residential, small business and non-profit customers.
In April 2021, legislation wasIowa tax reform enacted in Iowa prohibiting counties and cities from regulating the sale of natural gas and propane.March 2022.

RESULTS OF OPERATIONS

Results of operations include financial information prepared in accordance with GAAP as well as utility electric margins and utility gas margins, which are not measures of financial performance under GAAP. Utility electric margins are defined as electric revenues less electric production fuel, purchased power and electric transmission service expenses. Utility gas margins are defined as gas revenues less cost of gas sold. Utility electric margins and utility gas margins are non-GAAP financial measures because they exclude other utility and non-utility revenues, other operation and maintenance expenses, depreciation and amortization expenses, and taxes other than income tax expense.

Management believes that utility electric and gas margins provide a meaningful basis for evaluating and managing utility operations since electric production fuel, purchased power and electric transmission service expenses and cost of gas sold are generally passed through to customers, and therefore, result in changes to electric and gas revenues that are comparable to changes in such expenses. The presentation of utility electric and gas margins herein is intended to provide supplemental information for investors regarding operating performance. These utility electric and gas margins may not be comparable to how other entities define utility electric and gas margin. Furthermore, these measures are not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance.

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Additionally, the table below includes 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 segment 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.

Financial Results Overview - Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended March 31 were as follows (dollars in millions, except per share amounts):
2021202020222021
IncomeEPSIncome (Loss)EPSIncomeEPSIncome (Loss)EPS
Utilities and Corporate ServicesUtilities and Corporate Services$166$0.66$175$0.72Utilities and Corporate Services$183$0.73$166$0.66
ATC HoldingsATC Holdings80.0380.03ATC Holdings80.0380.03
Non-utility and ParentNon-utility and Parent(3)(0.01)(13)(0.05)Non-utility and Parent10.01(3)(0.01)
Alliant Energy ConsolidatedAlliant Energy Consolidated$171$0.68$170$0.70Alliant Energy Consolidated$192$0.77$171$0.68

Alliant Energy’s Utilities and Corporate Services net income decreasedincreased by $9$17 million for the three-month period, primarily due to timing of income taxes, higher depreciation expense and lower allowance for funds used during construction. These items were partially offset byAFUDC, higher earnings resulting from IPL’s and WPL’s increasing rate base, and higher retail electric and gas sales due to temperatures in the first quarter of 2021favorable temperature impacts compared to the first quarter of 2020.

Alliant Energy’s Non-utility and Parent net income increased by $10 million for the three-month period primarily due to a credit loss charge in the first quarter of 2020 related to legacy guarantees associated with an affiliate of Whiting Petroleum.2021, as well as higher temperature-normalized sales.

For the three months ended March 31, operating income and a reconciliation of utility electric and gas margins to the most directly comparable GAAP measure, operating income, was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Three MonthsThree Months202120202021202020212020Three Months202220212022202120222021
Operating incomeOperating income$198$188$103$97$90$94Operating income$248$198$110$103$131$90
Electric utility revenuesElectric utility revenues$701$730$386$425$315$305Electric utility revenues$773$701$400$386$373$315
Electric production fuel and purchased power expensesElectric production fuel and purchased power expenses(133)(184)(59)(106)(74)(78)Electric production fuel and purchased power expenses(168)(133)(67)(59)(101)(74)
Electric transmission service expenseElectric transmission service expense(134)(122)(92)(84)(42)(38)Electric transmission service expense(138)(134)(97)(92)(41)(42)
Utility Electric Margin (non-GAAP)Utility Electric Margin (non-GAAP)434424235235199189Utility Electric Margin (non-GAAP)467434236235231199
Gas utility revenuesGas utility revenues17015291837969Gas utility revenues2621701399112379
Cost of gas soldCost of gas sold(100)(85)(50)(44)(50)(41)Cost of gas sold(168)(100)(85)(50)(83)(50)
Utility Gas Margin (non-GAAP)Utility Gas Margin (non-GAAP)706741392928Utility Gas Margin (non-GAAP)947054414029
Other utility revenuesOther utility revenues1312121111Other utility revenues111311121
Non-utility revenuesNon-utility revenues1722Non-utility revenues2217
Other operation and maintenance expensesOther operation and maintenance expenses(146)(163)(77)(87)(59)(54)Other operation and maintenance expenses(153)(146)(83)(77)(58)(59)
Depreciation and amortization expensesDepreciation and amortization expenses(164)(146)(94)(86)(69)(59)Depreciation and amortization expenses(166)(164)(94)(94)(70)(69)
Taxes other than income tax expenseTaxes other than income tax expense(26)(28)(14)(15)(11)(11)Taxes other than income tax expense(27)(26)(14)(14)(12)(11)
Operating incomeOperating income$198$188$103$97$90$94Operating income$248$198$110$103$131$90
Operating Income Variances - Variances between periods in operating income for the three months ended March 31, 20212022 compared to the same period in 20202021 were as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Total higher utility electric margin variance (Refer to details below)Total higher utility electric margin variance (Refer to details below)$10$—$10Total higher utility electric margin variance (Refer to details below)$33$1$32
Total higher utility gas margin variance (Refer to details below)Total higher utility gas margin variance (Refer to details below)321Total higher utility gas margin variance (Refer to details below)241311
Total lower (higher) other operation and maintenance expenses variance (Refer to details below)1710(5)
Higher depreciation and amortization expense primarily due to additional plant in service in 2020 and 2021, including IPL’s new wind generation, and WPL’s West Riverside Energy Center and Kossuth wind farm(18)(8)(10)
Total (higher) lower other operation and maintenance expenses variance (Refer to details below)Total (higher) lower other operation and maintenance expenses variance (Refer to details below)(7)(6)1
Higher depreciation and amortization expense primarily due to additional plant in service in 2021 and 2022Higher depreciation and amortization expense primarily due to additional plant in service in 2021 and 2022(2)(1)
OtherOther(2)2Other2(1)(2)
$10$6($4)$50$7$41

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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 months ended March 31 were as follows:
Alliant EnergyAlliant EnergyElectricGasAlliant EnergyElectricGas
RevenuesMWhs SoldRevenuesDths SoldRevenuesMWhs SoldRevenuesDths Sold
2021202020212020202120202021202020222021202220212022202120222021
RetailRetail$636$6596,2726,125$157$14023,43122,022Retail$692$6366,3886,272$248$15726,09523,431
Sales for resaleSales for resale45571,0711,879N/AN/AN/AN/ASales for resale68451,9451,071N/AN/AN/AN/A
Transportation/OtherTransportation/Other20141918131224,69028,816Transportation/Other13201719141329,87724,690
$701$7307,3628,022$170$15248,12150,838$773$7018,3507,362$262$17055,97248,121
IPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20212020202120202021202020212020
Retail$361$3883,5823,482$82$7512,13811,621
Sales for resale11282871,251N/AN/AN/AN/A
Transportation/Other14910109811,17811,294
$386$4253,8794,743$91$8323,31622,915
WPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20212020202120202021202020212020
Retail$275$2712,6902,643$75$6511,29310,401
Sales for resale3429784628N/AN/AN/AN/A
Transportation/Other65984413,51217,522
$315$3053,4833,279$79$6924,80527,923
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IPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20222021202220212022202120222021
Retail$379$3613,6513,582$130$8213,60112,138
Sales for resale1311597287N/AN/AN/AN/A
Transportation/Other8148109912,02011,178
$400$3864,2563,879$139$9125,62123,316
WPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20222021202220212022202120222021
Retail$313$2752,7372,690$118$7512,49411,293
Sales for resale55341,348784N/AN/AN/AN/A
Transportation/Other56995417,85713,512
$373$3154,0943,483$123$7930,35124,805

Sales Trends and Temperatures - Alliant Energy’s retail electric and gas sales volumes increased 2% and 6%11%, respectively, for the three months ended March 31, 20212022 compared to the same period in 2020,2021, primarily due to changes in temperatures, COVID-19 impacts in Alliant Energy’s service territories, partially offset by2021 and increases in the impact on salesnumber of the additional day due to leap year in 2020.customers.

Estimated increases (decreases) to electric and gas margins from the impacts of temperatures for the three months ended March 31 were as follows (in millions):
Electric MarginsGas MarginsElectric MarginsGas Margins
20212020Change20212020Change20222021Change20222021Change
IPLIPL$2($3)$5$2($2)$4IPL$5$2$3$3$2$1
WPLWPL1(3)4(1)1WPL21111
Total Alliant EnergyTotal Alliant Energy$3($6)$9$2($3)$5Total Alliant Energy$7$3$4$4$2$2

Electric Sales for Resale - Alliant Energy’s and IPL’s electricElectric sales for resale volume changes were largely 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 sales for resale revenues were largely offset by changes in fuel-related costs, and therefore, did not have a significant impact on electric margins.

Gas Transportation/Other - Alliant Energy's and WPL's gasGas transportation/other sales volume changes were largely due to changes in the gas volumes supplied to WPL'sAlliant Energy’s natural gas-fired EGUs caused by the availability and dispatch of such EGUs. Changes in these transportation/other revenues did not have a significant impact on gas margins.

Utility Electric Margin Variances - The following items contributed to increased (decreased) utility electric margins for the three months ended March 31, 20212022 compared to the same period in 20202021 as follows (in millions):
Alliant EnergyIPLWPL
Higher revenue requirements due to increasing rate base (a) (b)$13$10$3
Estimated changes in sales volumes caused by temperatures954
Lower revenues at IPL due to changes in credits on customers’ bills related to excess deferred income tax benefits amortization through the tax benefit rider (offset by changes in income tax)(7)(7)
Lower revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)(5)(5)
Other(3)3
$10$—$10
Alliant EnergyIPLWPL
Higher revenue requirements at WPL due to increasing rate base (a)$26$—$26
Higher revenues at IPL due to changes in credits on customers’ bills related to excess deferred income tax benefits amortization through the tax benefit rider (offset by changes in income tax)66
Estimated changes in sales volumes caused by temperatures431
Lower revenues at IPL due to changes in the renewable energy rider (offset by changes in income tax)(12)(12)
Lower revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)(2)(2)
Other (includes higher temperature-normalized sales in 2022)1165
$33$1$32

(a)In December 2021, the PSCW issued an order authorizing annual base rate increases of $114 million and $15 million for WPL’s retail electric and gas customers, respectively, covering the 2022/2023 forward-looking Test Period, which was based on a stipulated agreement between WPL and certain stakeholders. The key drivers for the annual base rate increases include higher retail fuel-related costs in 2022, lower excess deferred income tax benefits in 2022 and 2023 compared to 2021, and revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation. Retail electric rate changes were effective on January 1, 2022 and extend through the end of 2023. Retail gas rate changes were effective on January 1, 2022 and extend through the end of 2022. The higher fuel expense costs are recognized in electric margin and the lower amount of excess deferred income tax benefits is recognized as a reduction in income tax.

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(a)IPL’s final retail electric base rate increase was effective February 26, 2020. Effective with final rates, the recovery of, and return on, IPL’s new wind generation placed in service in 2019 and 2020 is provided through the renewable energy rider. The final rate increase includes a reduction for anticipated production tax credits for IPL’s new wind generation. This reduction is expected to be offset by a reduction in income tax expense resulting from production tax credits recognized from this new wind generation. In September 2020, IPL made a buyout payment of $110 million in exchange for shortening the terms of its DAEC PPA by 5 years. The higher revenue requirements from the buyout payment, including a return on such costs, is being recovered from IPL’s retail customers from 2021 through the end of 2025.
(b)In December 2020, the PSCW issued an order authorizing WPL to maintain its current retail electric base rates through the end of 2021. WPL will utilize anticipated fuel-related cost savings and excess deferred income tax benefits in 2021 to offset the revenue requirement impacts of increasing electric rate base, including the Kossuth wind farm, which was placed in service in October 2020. The additional amount of excess deferred income tax benefits is recognized as a reduction in income tax expense.

Utility Gas Margin Variances - The following items contributed to increased (decreased) utility gas margins for the three months ended March 31, 20212022 compared to the same period in 20202021 as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)$9$9$—
Higher revenue requirements at WPL due to increasing rate base (refer to (a) above)Higher revenue requirements at WPL due to increasing rate base (refer to (a) above)77
Estimated changes in sales volumes caused by temperaturesEstimated changes in sales volumes caused by temperatures211
Other (includes higher temperature-normalized sales in 2022)Other (includes higher temperature-normalized sales in 2022)633
$24$13$11
Estimated changes in sales volumes caused by temperatures$5$4$1
Other(2)(2)
$3$2$1

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, 20212022 compared to the same period in 20202021 as follows (in millions):
Alliant EnergyIPLWPL
Credit loss charge in 2020 related to guarantees for an affiliate of Whiting Petroleum$8$—$—
Lower bad debt expense at IPL77
Lower energy efficiency expense at IPL (primarily offset by lower revenues)55
Other(3)(2)(5)
$17$10($5)
Alliant EnergyIPLWPL
Higher energy efficiency expense at IPL (primarily offset by higher revenues)($9)($9)$—
Other231
($7)($6)$1

Other Income and Deductions Variances - The following items contributed to (increased) decreased other income and deductions for the three months ended March 31, 20212022 compared to the same period in 20202021 as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Lower allowance for funds used during construction primarily due to changes in construction work in progress balances related to IPL’s new wind generation, and WPL’s West Riverside Energy Center and Kossuth wind farm placed in service in 2020($19)($8)($11)
Higher interest expense primarily due to financings completed in 2021Higher interest expense primarily due to financings completed in 2021($5)($2)($1)
Higher AFUDC primarily due to changes in construction work in progress balances related to WPL’s solar generationHigher AFUDC primarily due to changes in construction work in progress balances related to WPL’s solar generation717
OtherOther1(2)Other21
($18)($8)($13)$4($1)$7

Income Taxes - Refer to Note 8 for details of effective income tax rates.

Preferred Dividend Requirements of IPL - Alliant Energy’s and IPL’s preferred dividend requirements decreased for the three months ended March 31, 2022 compared to the same period in 2021 a due to the redemption of IPL’s 5.1% cumulative preferred stock in December 2021.

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 20202021 Form 10-K has not changed materially, except as described below.

Liquidity Position - At March 31, 2021,2022, Alliant Energy had $14$67 million of cash and cash equivalents, $664$724 million ($262331 million at the parent company, $250 million at IPL and $152$143 million at WPL) of available capacity under the single revolving credit facility and $15$109 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Capital structures at March 31, 2022 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE)):
lnt-20220331_g2.jpglnt-20220331_g3.jpglnt-20220331_g4.jpg
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Capital Structure - Capital structures at March 31, 2021 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE); IPL’s Preferred Stock (PS)):
lnt-20210331_g2.jpglnt-20210331_g3.jpglnt-20210331_g4.jpg
Cash Flows - Selected information from the cash flows statements was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
202120202021202020212020202220212022202120222021
Cash, cash equivalents and restricted cash, January 1Cash, cash equivalents and restricted cash, January 1$56$18$50$9$3$4Cash, cash equivalents and restricted cash, January 1$40$56$34$50$2$3
Cash flows from (used for):Cash flows from (used for):Cash flows from (used for):
Operating activitiesOperating activities145160(45)25148148Operating activities25114589(45)167148
Investing activitiesInvesting activities(38)(179)98(53)(119)(124)Investing activities(223)(38)1898(217)(119)
Financing activitiesFinancing activities(145)60(92)44(30)(5)Financing activities3(145)(79)(92)52(30)
Net increase (decrease)Net increase (decrease)(38)41(39)16(1)19Net increase (decrease)31(38)28(39)2(1)
Cash, cash equivalents and restricted cash, March 31Cash, cash equivalents and restricted cash, March 31$18$59$11$25$2$23Cash, cash equivalents and restricted cash, March 31$71$18$62$11$4$2

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the three months ended March 31, 20212022 compared to the same period in 20202021 (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher collections from WPL’s increasing base rateHigher collections from WPL’s increasing base rate$33$—$33
Natural gas cost payments from extreme temperatures in February 2021 resulting in under-recovered natural gas costs at IPL in 2021Natural gas cost payments from extreme temperatures in February 2021 resulting in under-recovered natural gas costs at IPL in 20212020
Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas salesIncreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales642
Higher natural gas cost payments from extreme temperatures in February 2021 resulting in under-recovered natural gas costs at IPL (Refer to Note 2)
($20)($20)$—
Changes in credits issued to IPL’s retail electric customers through its tax benefit rider related to excess deferred income taxes amortization(7)(7)
Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales1495
Higher collections from IPL’s increasing base rate1010
Changes in interest paymentsChanges in interest payments(3)(2)
Changes in income taxes paid/refundedChanges in income taxes paid/refunded(7)
Timing of intercompany payments and receiptsTiming of intercompany payments and receipts(56)(15)Timing of intercompany payments and receipts6016
Other (primarily due to other changes in working capital)Other (primarily due to other changes in working capital)(12)(6)10Other (primarily due to other changes in working capital)5057(30)
($15)($70)$—$106$134$19

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the three months ended March 31, 20212022 compared to the same period in 20202021 (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Changes in the amount of cash receipts on sold receivablesChanges in the amount of cash receipts on sold receivables$86$86$—Changes in the amount of cash receipts on sold receivables($94)($94)$—
Lower utility construction and acquisition expenditures (a)64595
(Higher) lower utility construction and acquisition expenditures (a)(Higher) lower utility construction and acquisition expenditures (a)(93)10(104)
OtherOther(9)6Other246
$141$151$5($185)($80)($98)

(a)Largely due to higher expenditures for WPL’s solar generation, partially offset by lower expenditures for IPL’s and WPL’s expansion of windelectric and gas distribution systems.

Construction and Acquisition Expenditures - Alliant Energy, IPL and WPL are currently evaluating potential impacts from cost pressures prevalent in the solar generation and battery storage markets, as well as the U.S. Department of Commerce investigation discussed in “2022 Highlights,” on the timing and estimated costs for IPL’s and WPL’s West Riverside Energy Center, partially offset by higher expenditures for WPL’s solar generation.planned development and acquisition of additional renewable energy, which could impact their anticipated future construction and acquisition expenditures.

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the three months ended March 31, 2022 compared to the same period in 2021 (in millions):
Alliant EnergyIPLWPL
Higher net proceeds from issuance of long-term debt$650$—$—
Higher payments to retire long-term debt(300)
Net changes in the amount of commercial paper outstanding(186)30
(Higher) lower common stock dividends(5)20(2)
Higher capital contributions from WPL’s parent company, Alliant Energy55
Other(11)(7)(1)
$148$13$82

IPL and WPL Solar Project Tax Equity Financing - Alliant Energy, IPL and WPL are currently evaluating potential impacts from cost pressures prevalent in the solar generation and battery storage markets, as well as the U.S. Department of Commerce investigation discussed in “2022 Highlights,” on the timing and estimated costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, which could result in changes to their proposed solar project tax equity financing.

Common Stock Issuances - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2022.
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Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the three months ended March 31, 2021 compared to the same period in 2020 (in millions):
Alliant EnergyIPLWPL
Lower net proceeds from issuance of long-term debt($300)$—$—
Lower net proceeds from common stock issuances(220)
Lower (higher) common stock dividends(9)(41)1
Lower payments to retire long-term debt300
Net changes in the amount of commercial paper and other short-term borrowings outstanding14(123)
Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy(100)100
Other105(3)
($205)($136)($25)

Common Stock IssuancesLong-term Debt - Refer to Note 56(b) for discussion of common stock issuances byAEF’s issuance of long-term debt in 2022. AEF’s current term loan credit agreement that expires in March 2024 includes an option to increase the amount outstanding up to $400 million in aggregate with the same maturity, subject to bank approval, and includes substantially the same financial covenants that are included in Alliant Energy in 2021.Energy’s credit facility agreement.

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 20202021 Form 10-K and has not changed materially from the items reported in the 20202021 Form 10-K, except for the items described in Notes 3, 6 and 1212.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Quantitative and Qualitative Disclosures About Market Risk are reported in the 20202021 Form 10-K and have not changed materially.

ITEM 4. CONTROLS AND PROCEDURES

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 of March 31, 20212022 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, 2021.2022.

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, 20212022 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

None. Securities and Exchange CommissionSEC regulations require Alliant Energy, IPL and WPL to disclose information about certain proceedings arising under federal, state or local environmental provisions when a governmental authority is a party to the proceedings and such proceedings involve potential monetary sanctions that Alliant Energy, IPL and WPL reasonably believe will exceed a specified threshold. Pursuant to the Securities and Exchange CommissionSEC regulations, Alliant Energy, IPL and WPL use a threshold of $1 million for purposes of determining whether disclosure of any such proceedings is required. Applying this threshold, there are no environmental matters to disclose for this period.

ITEM 1A. RISK FACTORS

The risk factors described in Item 1A in the 20202021 Form 10-K have not changed materially.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

A summary of Alliant Energy common stock repurchases for the quarter ended March 31, 20212022 was as follows:
Total NumberAverage PriceTotal Number of SharesMaximum Number (or Approximate
of SharesPaid PerPurchased as Part ofDollar Value) of Shares That May
PeriodPurchased (a)SharePublicly Announced PlanYet Be Purchased Under the Plan (a)
January 1 through January 314,432$49.35N/A
February 1 through February 283,16147.85N/A
March 1 through March 3148448.77N/A
8,07748.73

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Total NumberAverage PriceTotal Number of SharesMaximum Number (or Approximate
of SharesPaid PerPurchased as Part ofDollar Value) of Shares That May
PeriodPurchased (a)SharePublicly Announced PlanYet Be Purchased Under the Plan (a)
January 1 through January 314,227$60.98N/A
February 1 through February 282,91856.38N/A
March 1 through March 3159460.58N/A
7,73959.22

(a)All shares were purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan. There is no limit on the number of shares of Alliant Energy common stock that may be held under the Deferred Compensation Plan, which currently does not have an expiration date.

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ITEM 6. EXHIBITS

The following Exhibits are filed herewith.herewith or incorporated herein by reference.
Exhibit NumberDescription
4.1
10.1
31.1
31.2
31.3
31.4
31.5
31.6
32.1
32.2
32.3
101.INSInline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCHInline XBRL Taxonomy Extension Schema Document
101.CALInline XBRL Taxonomy Extension Calculation Linkbase Document
101.LABInline XBRL Taxonomy Extension Label Linkbase Document
101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document
101.DEFInline XBRL Taxonomy Extension Definition Linkbase Document
104Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized on the 7th29th day of May 2021.April 2022.

ALLIANT ENERGY CORPORATION
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)
INTERSTATE POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)
WISCONSIN POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)

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