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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, 2023

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

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, 2023:

Alliant Energy Corporation, Common Stock, $0.01 par value, 251,387,788 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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TABLE OF CONTENTS

	Page
Definitions	1
Forward-looking Statements	1
Part I. Financial Information	3
Item 1. Condensed Consolidated Financial Statements (Unaudited)	3
Alliant Energy Corporation	3
Interstate Power and Light Company	6
Wisconsin Power and Light Company	9
Combined Notes to Condensed Consolidated Financial Statements	12
1. Summary of Significant Accounting Policies	12
2. Regulatory Matters	12
3. Property, Plant and Equipment	13
4. Receivables	13
5. Investments	13
6. Common Equity	13
7. Debt	15
8. Revenues	16
9. Income Taxes	16
10. Benefit Plans	16
11. Derivative Instruments	17
12. Fair Value Measurements	19
13. Commitments and Contingencies	20
14. Segments of Business	22
15. Related Parties	22
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations	23
Item 3. Quantitative and Qualitative Disclosures About Market Risk	28
Item 4. Controls and Procedures	28
Part II. Other Information	28
Item 1. Legal Proceedings	28
Item 1A. Risk Factors	29
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds	29
Item 6. Exhibits	29
Signatures	30

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DEFINITIONS

The following abbreviations or acronyms used in this report are defined below:

Abbreviation or Acronym	Definition	Abbreviation or Acronym	Definition
2022 Form 10-K	Combined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2022	IUB	Iowa Utilities Board
AEF	Alliant Energy Finance, LLC	MDA	Management’s Discussion and Analysis of Financial Condition and Results of Operations
AFUDC	Allowance for funds used during construction	MISO	Midcontinent Independent System Operator, Inc.
Alliant Energy	Alliant Energy Corporation	MW	Megawatt
ATC	American Transmission Company LLC	MWh	Megawatt-hour
ATC Holdings	Interest in American Transmission Company LLC and ATC Holdco LLC	N/A	Not applicable
Corporate Services	Alliant Energy Corporate Services, Inc.	Note(s)	Combined Notes to Condensed Consolidated Financial Statements
Dth	Dekatherm	OPEB	Other postretirement benefits
EGU	Electric generating unit	PPA	Purchased power agreement
EPA	U.S. Environmental Protection Agency	PSCW	Public Service Commission of Wisconsin
EPS	Earnings per weighted average common share	SEC	Securities and Exchange Commission
Financial Statements	Condensed Consolidated Financial Statements	U.S.	United States of America
FTR	Financial transmission right	West Riverside	West Riverside Energy Center and Solar Facility
GAAP	U.S. generally accepted accounting principles	Whiting Petroleum	Whiting Petroleum Corporation
IPL	Interstate Power and Light Company	WPL	Wisconsin 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 cyber security incidents or attacks on our physical infrastructure, 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;

•inflation and higher interest rates;

•changes in the price of delivered natural gas, transmission, purchased electricity and coal, particularly during elevated market prices, and any resulting changes to counterparty credit risk, due to shifts in supply and demand caused by market conditions, regulations and MISO’s seasonal resource adequacy process;

•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, capacity costs, deferred expenditures, deferred tax assets, tax expense, interest 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;

•the ability to obtain regulatory approval for construction projects with acceptable conditions;

•the ability to complete construction of renewable 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 and any decisions made regarding 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;

•the ability to utilize tax credits generated to date, and those that may be generated in the future, before they expire, as well as the ability to transfer tax credits that may be generated in the future at adequate pricing;

•disruptions to ongoing operations and the supply of materials, services, equipment and commodities needed to construct solar generation, battery storage and electric and gas distribution projects, which may result from geopolitical issues, supplier manufacturing constraints, labor issues or transportation issues, and thus affect the ability to meet capacity requirements and result in increased capacity expense;

•federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;

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•the impacts of changes in the tax code, including tax rates, minimum tax rates, and adjustments made to deferred tax assets and liabilities;

•employee workforce factors, including the ability to hire and retain employees with specialized skills, impacts from employee retirements, changes in key executives, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;

•disruptions in the supply and delivery of natural gas, purchased electricity and coal;

•changes to the creditworthiness of, or performance of obligations by, counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;

•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;

•impacts that terrorist attacks 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;

•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;

•continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;

•changes to MISO’s resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements that may impact how and when new and existing generating facilities, including IPL’s and WPL’s additional solar generation, may be accredited with energy capacity, and may require IPL and WPL to adjust their current resource plans, to add resources to meet the requirements of MISO’s new process, or procure capacity in the market whereby such costs might not be recovered in rates;

•the direct or indirect effects resulting from the ongoing novel coronavirus (COVID-19) pandemic and the spread of variant strains;

•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 changes to Cross-State Air Pollution Rule emissions allowances and 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;

•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 operating, fuel-related and capital 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 construction activities, 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, including settlement losses related to pension plans;

•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 changes in valuations of the assets held, as well as 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;

•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 2022 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.

Available Information. Alliant Energy routinely posts important information on its website and considers the Investors section of its website, www.alliantenergy.com/investors, a channel of distribution for material information. Information contained on Alliant Energy’s website is not incorporated herein.

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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,
	2023	2022
	(in millions, except per share amounts)
Revenues:
Electric utility	$768	$773
Gas utility	276	262
Other utility	11	11
Non-utility	22	22
Total revenues	1,077	1,068
Operating expenses:
Electric production fuel and purchased power	157	168
Electric transmission service	146	138
Cost of gas sold	181	168
Other operation and maintenance	174	153
Depreciation and amortization	166	166
Taxes other than income taxes	31	27
Total operating expenses	855	820
Operating income	222	248
Other (income) and deductions:
Interest expense	94	74
Equity income from unconsolidated investments, net	(17)	(15)
Allowance for funds used during construction	(19)	(11)
Other	3	—
Total other (income) and deductions	61	48
Income before income taxes	161	200
Income tax expense (benefit)	(2)	8
Net income attributable to Alliant Energy common shareowners	$163	$192
Weighted average number of common shares outstanding:
Basic	251.2	250.6
Diluted	251.4	250.9
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)	$0.65	$0.77

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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ALLIANT ENERGY CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

	March 31, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$157	$20
Accounts receivable, less allowance for expected credit losses	428	516
Production fuel, at weighted average cost	60	53
Gas stored underground, at weighted average cost	64	132
Materials and supplies, at weighted average cost	158	140
Regulatory assets	193	166
Other	132	223
Total current assets	1,192	1,250
Property, plant and equipment, net	16,396	16,247
Investments:
ATC Holdings	363	358
Other	206	201
Total investments	569	559
Other assets:
Regulatory assets	1,887	1,880
Deferred charges and other	196	227
Total other assets	2,083	2,107
Total assets	$20,240	$20,163

LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt	$808	$408
Commercial paper	60	642
Other short-term borrowings	50	—
Accounts payable	518	756
Regulatory liabilities	129	206
Other	343	351
Total current liabilities	1,908	2,363
Long-term debt, net (excluding current portion)	8,132	7,668
Other liabilities:
Deferred tax liabilities	1,957	1,943
Regulatory liabilities	1,102	1,118
Pension and other benefit obligations	273	277
Other	540	518
Total other liabilities	3,872	3,856
Commitments and contingencies (Note 13)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 251,387,788 and 251,134,966 shares outstanding	3	3
Additional paid-in capital	2,780	2,777
Retained earnings	3,559	3,509
Accumulated other comprehensive loss	(1)	—
Shares in deferred compensation trust - 394,363 and 402,134 shares at a weighted average cost of $33.12 and $32.63 per share	(13)	(13)
Total Alliant Energy Corporation common equity	6,328	6,276
Total liabilities and equity	$20,240	$20,163

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,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$163	$192
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	166	166
Other	(6)	12
Other changes in assets and liabilities:
Accounts receivable	(86)	(161)
Gas stored underground	68	55
Derivative assets	115	(85)
Regulatory assets	(32)	19
Accounts payable	(97)	(37)
Regulatory liabilities	(95)	92
Other	(8)	(2)
Net cash flows from operating activities	188	251
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business	(417)	(307)
Other	(34)	(23)
Cash receipts on sold receivables	173	115
Proceeds from sale of partial ownership interest in West Riverside	25	—
Other	(10)	(8)
Net cash flows used for investing activities	(263)	(223)
Cash flows from financing activities:
Common stock dividends	(113)	(107)
Proceeds from issuance of long-term debt	862	650
Payments to retire long-term debt	—	(300)
Net change in commercial paper and other short-term borrowings	(532)	(239)
Other	(5)	(1)
Net cash flows from financing activities	212	3
Net increase in cash, cash equivalents and restricted cash	137	31
Cash, cash equivalents and restricted cash at beginning of period	24	40
Cash, cash equivalents and restricted cash at end of period	$161	$71
Supplemental cash flows information:
Cash paid during the period for:
Interest	($93)	($62)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$254	$134
Beneficial interest obtained in exchange for securitized accounts receivable	$153	$227

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,
	2023	2022
	(in millions)
Revenues:
Electric utility	$388	$400
Gas utility	150	139
Steam and other	11	11
Total revenues	549	550
Operating expenses:
Electric production fuel and purchased power	47	67
Electric transmission service	104	97
Cost of gas sold	95	85
Other operation and maintenance	95	83
Depreciation and amortization	96	94
Taxes other than income taxes	16	14
Total operating expenses	453	440
Operating income	96	110
Other (income) and deductions:
Interest expense	37	37
Allowance for funds used during construction	(3)	(3)
Other	1	—
Total other (income) and deductions	35	34
Income before income taxes	61	76
Income tax benefit	(11)	(11)
Net income	$72	$87

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, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$35	$15
Accounts receivable, less allowance for expected credit losses	191	259
Production fuel, at weighted average cost	26	23
Gas stored underground, at weighted average cost	26	60
Materials and supplies, at weighted average cost	92	83
Regulatory assets	75	85
Other	49	93
Total current assets	494	618
Property, plant and equipment, net	8,112	8,046
Other assets:
Regulatory assets	1,308	1,301
Deferred charges and other	93	110
Total other assets	1,401	1,411
Total assets	$10,007	$10,075

LIABILITIES AND EQUITY
Current liabilities:
Accounts payable	$222	$239
Accounts payable to associated companies	37	28
Accrued taxes	59	52
Accrued interest	35	35
Regulatory liabilities	73	114
Other	92	113
Total current liabilities	518	581
Long-term debt, net	3,647	3,646
Other liabilities:
Deferred tax liabilities	1,053	1,047
Regulatory liabilities	624	640
Pension and other benefit obligations	61	62
Other	294	291
Total other liabilities	2,032	2,040
Commitments and contingencies (Note 13)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding	33	33
Additional paid-in capital	2,807	2,807
Retained earnings	970	968
Total Interstate Power and Light Company common equity	3,810	3,808
Total liabilities and equity	$10,007	$10,075

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,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$72	$87
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	96	94
Deferred tax expense and tax credits	3	15
Other	(2)	(2)
Other changes in assets and liabilities:
Accounts receivable	(106)	(128)
Income tax refunds receivable	(7)	(17)
Gas stored underground	34	29
Derivative assets	69	(43)
Accounts payable	(56)	(8)
Regulatory liabilities	(59)	59
Other	(20)	3
Net cash flows from operating activities	24	89
Cash flows from investing activities:
Construction and acquisition expenditures	(101)	(96)
Cash receipts on sold receivables	173	115
Other	(2)	(1)
Net cash flows from investing activities	70	18
Cash flows used for financing activities:
Common stock dividends	(70)	(81)
Other	(4)	2
Net cash flows used for financing activities	(74)	(79)
Net increase in cash, cash equivalents and restricted cash	20	28
Cash, cash equivalents and restricted cash at beginning of period	15	34
Cash, cash equivalents and restricted cash at end of period	$35	$62
Supplemental cash flows information:
Cash paid during the period for:
Interest	($37)	($37)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$98	$27
Beneficial interest obtained in exchange for securitized accounts receivable	$153	$227

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,
	2023	2022
	(in millions)
Revenues:
Electric utility	$380	$373
Gas utility	126	123
Total revenues	506	496
Operating expenses:
Electric production fuel and purchased power	109	101
Electric transmission service	42	41
Cost of gas sold	86	83
Other operation and maintenance	66	58
Depreciation and amortization	68	70
Taxes other than income taxes	14	12
Total operating expenses	385	365
Operating income	121	131
Other (income) and deductions:
Interest expense	36	27
Allowance for funds used during construction	(16)	(9)
Other	1	—
Total other (income) and deductions	21	18
Income before income taxes	100	113
Income tax expense	12	21
Net income	$88	$92

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, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$86	$5
Accounts receivable, less allowance for expected credit losses	225	244
Production fuel, at weighted average cost	34	29
Gas stored underground, at weighted average cost	38	73
Materials and supplies, at weighted average cost	63	54
Regulatory assets	118	81
Prepaid gross receipts tax	31	42
Other	26	60
Total current assets	621	588
Property, plant and equipment, net	7,792	7,722
Other assets:
Regulatory assets	579	579
Deferred charges and other	82	98
Total other assets	661	677
Total assets	$9,074	$8,987

LIABILITIES AND EQUITY
Current liabilities:
Commercial paper	$60	$290
Accounts payable	233	456
Regulatory liabilities	56	92
Other	163	111
Total current liabilities	512	949
Long-term debt, net	3,067	2,770
Other liabilities:
Deferred tax liabilities	787	789
Regulatory liabilities	478	478
Pension and other benefit obligations	139	140
Other	378	370
Total other liabilities	1,782	1,777
Commitments and contingencies (Note 13)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding	66	66
Additional paid-in capital	2,413	2,233
Retained earnings	1,234	1,192
Total Wisconsin Power and Light Company common equity	3,713	3,491
Total liabilities and equity	$9,074	$8,987

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,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$88	$92
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	68	70
Other	(12)	(5)
Other changes in assets and liabilities:
Accounts receivable	19	(23)
Gas stored underground	35	26
Derivative assets	46	(42)
Regulatory assets	(37)	10
Accounts payable	(48)	(24)
Derivative liabilities	28	(2)
Regulatory liabilities	(35)	32
Accrued taxes	19	21
Other	14	12
Net cash flows from operating activities	185	167
Cash flows used for investing activities:
Construction and acquisition expenditures	(316)	(212)
Proceeds from sale of partial ownership interest in West Riverside	25	—
Other	(4)	(5)
Net cash flows used for investing activities	(295)	(217)
Cash flows from financing activities:
Common stock dividends	(46)	(44)
Capital contributions from parent	180	180
Proceeds from issuance of long-term debt	297	—
Net change in commercial paper	(230)	(79)
Other	(10)	(5)
Net cash flows from financing activities	191	52
Net increase in cash, cash equivalents and restricted cash	81	2
Cash, cash equivalents and restricted cash at beginning of period	5	2
Cash, cash equivalents and restricted cash at end of period	$86	$4
Supplemental cash flows information:
Cash paid during the period for:
Interest	($40)	($23)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$152	$104

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

11

Table of Contents

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 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 2022 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, 2023 are not necessarily indicative of results that may be expected for the year ending December 31, 2023.

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 and Cash Equivalents - At March 31, 2023, Alliant Energy’s, IPL’s and WPL’s cash and cash equivalents included $148 million, $30 million and $83 million of money market fund investments, respectively, with interest rates of 5%.

NOTE 2. REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy		IPL		WPL
	March 31, 2023	December 31, 2022	March 31, 2023	December 31, 2022	March 31, 2023	December 31, 2022
Tax-related	$942	$929	$857	$848	$85	$81
Pension and OPEB costs	385	392	193	197	192	195
Asset retirement obligations	156	151	115	110	41	41
Commodity cost recovery	152	160	4	1	148	159
Derivatives	101	84	37	48	64	36
Assets retired early	67	70	51	53	16	17
IPL’s Duane Arnold Energy Center PPA amendment	60	66	60	66	—	—
WPL’s Western Wisconsin gas distribution expansion investments	48	48	—	—	48	48
Other	169	146	66	63	103	83
	$2,080	$2,046	$1,383	$1,386	$697	$660

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the three months ended March 31, 2023, which result in comparable changes to regulatory assets/liabilities on the balance sheets.

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy		IPL		WPL
	March 31, 2023	December 31, 2022	March 31, 2023	December 31, 2022	March 31, 2023	December 31, 2022
Tax-related	$575	$579	$302	$303	$273	$276
Cost of removal obligations	403	398	261	259	142	139
Derivatives	117	210	64	115