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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, 2021

or

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


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:
Alliant Energy Corporation, Common Stock, $0.01 par value, 250,134,552 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
2020 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, LLCIPLInterstate Power and Light Company
Alliant EnergyAlliant Energy CorporationIUBIowa Utilities Board
ATCAmerican Transmission Company LLCMDAManagement’s Discussion and Analysis of Financial Condition and Results of Operations
ATC HoldingsInterest in American Transmission Company LLC and ATC Holdco LLCMISOMidcontinent Independent System Operator, Inc.
Corporate ServicesAlliant Energy Corporate Services, Inc.MWMegawatt
COVID-19Novel coronavirusMWhMegawatt-hour
DAECDuane Arnold Energy CenterN/ANot applicable
DthDekathermNote(s)Combined Notes to Condensed Consolidated Financial Statements
EGUElectric generating unitOPEBOther postretirement benefits
EPAU.S. Environmental Protection AgencyPPAPurchased power agreement
EPSEarnings per weighted average common sharePSCWPublic Service Commission of Wisconsin
Federal Tax ReformTax Cuts and Jobs ActU.S.United States of America
FERCFederal Energy Regulatory CommissionWest RiversideWest Riverside Energy Center
Financial StatementsCondensed Consolidated Financial StatementsWhiting PetroleumWhiting Petroleum Corporation
FTRFinancial transmission rightWPLWisconsin 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 tax rates, including minimum tax rates, and adjustments made to deferred tax assets and liabilities;
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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;
weather effects on results of utility operations;
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;
the ability to complete construction of solar generation projects within the cost targets set by regulators and the ability to efficiently utilize the solar generation project tax benefits for the benefit of customers;
changes in the price of delivered natural gas, transmission, purchased electricity and coal due to shifts in supply and demand caused by market conditions and regulations;
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, 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 2020 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 Months
Ended March 31,
20212020
(in millions, except per share amounts)
Revenues:
Electric utility$701$730
Gas utility170152
Other utility1312
Non-utility1722
Total revenues901916
Operating expenses:
Electric production fuel and purchased power133184
Electric transmission service134122
Cost of gas sold10085
Other operation and maintenance146163
Depreciation and amortization164146
Taxes other than income taxes2628
Total operating expenses703728
Operating income198188
Other (income) and deductions:
Interest expense6969
Equity income from unconsolidated investments, net(15)(13)
Allowance for funds used during construction(4)(23)
Other21
Total other (income) and deductions5234
Income before income taxes146154
Income tax benefit(28)(19)
Net income174173
Preferred dividend requirements of Interstate Power and Light Company33
Net income attributable to Alliant Energy common shareowners$171$170
Weighted average number of common shares outstanding:
Basic250.0244.4
Diluted250.4244.6
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.68$0.70

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
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$14$54
Accounts receivable, less allowance for expected credit losses325412
Production fuel, at weighted average cost5766
Gas stored underground, at weighted average cost2546
Materials and supplies, at weighted average cost122105
Regulatory assets9581
Other117123
Total current assets755887
Property, plant and equipment, net14,35314,336
Investments:
ATC Holdings334331
Other160154
Total investments494485
Other assets:
Regulatory assets1,9121,929
Deferred charges and other8073
Total other assets1,9922,002
Total assets$17,594$17,710
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$308$8
Commercial paper336389
Accounts payable307377
Regulatory liabilities208249
Other249274
Total current liabilities1,4081,297
Long-term debt, net (excluding current portion)6,4716,769
Other liabilities:
Deferred tax liabilities1,8431,814
Regulatory liabilities1,0471,057
Pension and other benefit obligations495511
Other364374
Total other liabilities3,7493,756
Commitments and contingencies (Note 12)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 250,134,552 and 249,868,415 shares
32
Additional paid-in capital2,7122,704
Retained earnings3,0632,994
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)
Total Alliant Energy Corporation common equity5,7665,688
Cumulative preferred stock of Interstate Power and Light Company200200
Total equity5,9665,888
Total liabilities and equity$17,594$17,710

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 Months
Ended March 31,
20212020
(in millions)
Cash flows from operating activities:
Net income$174$173
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization
164146
Deferred tax benefit and tax credits(29)(23)
Other45
Other changes in assets and liabilities:
Accounts receivable(126)(119)
Regulatory liabilities(60)(38)
Deferred income taxes5850
Pension and other benefit obligations(16)(31)
Other(24)(3)
Net cash flows from operating activities145160
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business(214)(278)
Other(17)(11)
Cash receipts on sold receivables209123
Other(16)(13)
Net cash flows used for investing activities(38)(179)
Cash flows from (used for) financing activities:
Common stock dividends(102)(93)
Proceeds from issuance of common stock, net8228
Proceeds from issuance of long-term debt300
Payments to retire long-term debt(300)
Net change in commercial paper and other short-term borrowings(53)(67)
Other2(8)
Net cash flows from (used for) financing activities(145)60
Net increase (decrease) in cash, cash equivalents and restricted cash(38)41
Cash, cash equivalents and restricted cash at beginning of period5618
Cash, cash equivalents and restricted cash at end of period$18$59
Supplemental cash flows information:
Cash paid during the period for:
Interest($59)($65)
Significant non-cash investing and financing activities:
Accrued capital expenditures$64$156
Beneficial interest obtained in exchange for securitized accounts receivable$107$188

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 Months
Ended March 31,
20212020
(in millions)
Revenues:
Electric utility$386$425
Gas utility9183
Steam and other1211
Total revenues489519
Operating expenses:
Electric production fuel and purchased power59106
Electric transmission service9284
Cost of gas sold5044
Other operation and maintenance7787
Depreciation and amortization9486
Taxes other than income taxes1415
Total operating expenses386422
Operating income10397
Other (income) and deductions:
Interest expense3534
Allowance for funds used during construction(2)(10)
Other1
Total other (income) and deductions3325
Income before income taxes7072
Income tax benefit(12)(14)
Net income8286
Preferred dividend requirements33
Net income available for common stock$79$83
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
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$11$50
Accounts receivable, less allowance for expected credit losses130210
Production fuel, at weighted average cost4548
Gas stored underground, at weighted average cost820
Materials and supplies, at weighted average cost7363
Regulatory assets7352
Other5353
Total current assets393496
Property, plant and equipment, net7,8727,889
Other assets:
Regulatory assets1,4211,431
Deferred charges and other4033
Total other assets1,4611,464
Total assets$9,726$9,849
LIABILITIES AND EQUITY
Current liabilities:
Accounts payable$119$162
Accounts payable to associated companies45
Regulatory liabilities87103
Other131137
Total current liabilities337447
Long-term debt, net3,3463,345
Other liabilities:
Deferred tax liabilities1,0471,035
Regulatory liabilities
574573
Pension and other benefit obligations180186
Other300299
Total other liabilities2,1012,093
Commitments and contingencies (Note 12)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding
3333
Additional paid-in capital2,7522,752
Retained earnings957979
Total Interstate Power and Light Company common equity3,7423,764
Cumulative preferred stock200200
Total equity3,9423,964
Total liabilities and equity$9,726$9,849

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 Months
Ended March 31,
20212020
(in millions)
Cash flows from (used for) operating activities:
Net income$82$86
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortization9486
Other(3)(15)
Other changes in assets and liabilities:
Accounts receivable(133)(126)
Regulatory assets(16)(9)
Regulatory liabilities(19)1
Deferred income taxes1415
Other(64)(13)
Net cash flows from (used for) operating activities(45)25
Cash flows from (used for) investing activities:
Construction and acquisition expenditures(106)(165)
Cash receipts on sold receivables209123
Other(5)(11)
Net cash flows from (used for) investing activities98(53)
Cash flows from (used for) financing activities:
Common stock dividends(101)(60)
Capital contributions from parent100
Other94
Net cash flows from (used for) financing activities(92)44
Net increase (decrease) in cash, cash equivalents and restricted cash(39)16
Cash, cash equivalents and restricted cash at beginning of period509
Cash, cash equivalents and restricted cash at end of period$11$25
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest($37)($41)
Income taxes, net$7$
Significant non-cash investing and financing activities:
Accrued capital expenditures$31$92
Beneficial interest obtained in exchange for securitized accounts receivable$107$188

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 Months
Ended March 31,
20212020
(in millions)
Revenues:
Electric utility$315$305
Gas utility7969
Other11
Total revenues395375
Operating expenses:
Electric production fuel and purchased power7478
Electric transmission service4238
Cost of gas sold5041
Other operation and maintenance5954
Depreciation and amortization6959
Taxes other than income taxes1111
Total operating expenses305281
Operating income9094
Other (income) and deductions:
Interest expense2625
Allowance for funds used during construction(2)(13)
Other1
Total other (income) and deductions2512
Income before income taxes6582
Income tax benefit(19)(8)
Net income$84$90
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 liabilities
719702
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)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding
6666
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

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 Months
Ended March 31,
20212020
(in millions)
Cash flows from operating activities:
Net income$84$90
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization6959
Deferred tax benefit and tax credits(28)(11)
Other4(5)
Other changes in assets and liabilities:
Regulatory liabilities(41)(39)
Deferred income taxes4432
Other1622
Net cash flows from operating activities148148
Cash flows used for investing activities:
Construction and acquisition expenditures(108)(113)
Other(11)(11)
Net cash flows used for investing activities(119)(124)
Cash flows used for financing activities:
Common stock dividends(42)(43)
Capital contributions from parent12525
Net change in commercial paper and other short-term borrowings(109)14
Other(4)(1)
Net cash flows used for financing activities(30)(5)
Net increase (decrease) in cash, cash equivalents and restricted cash(1)19
Cash, cash equivalents and restricted cash at beginning of period34
Cash, cash equivalents and restricted cash at end of period$2$23
Supplemental cash flows information:
Cash paid during the period for:
Interest($21)($21)
Significant non-cash investing and financing activities:
Accrued capital expenditures$32$62

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. 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 on 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, 2021 are not necessarily indicative of results that may be expected for the year ending December 31, 2021.

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 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.

Regulatory liabilities 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$685$732$327$331$358$401
Cost of removal obligations371367242238129129
Electric transmission cost recovery676840392729
WPL’s West Riverside liquidated damages38383838
Derivatives2628182583
Other687334433430
$1,255$1,306$661$676$594$630

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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, IPL had $15 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):
20212020
Maximum outstanding aggregate cash proceeds$100$96
Average outstanding aggregate cash proceeds3024

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
March 31, 2021December 31, 2020
Customer accounts receivable$124$114
Unbilled utility revenues7492
Receivables sold to third party198206
Less: cash proceeds751
Deferred proceeds123