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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 June 30, 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 June 30, 2023:

Alliant Energy Corporation, Common Stock, $0.01 par value, 252,719,092 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	14
6. Common Equity	14
7. Debt	16
8. Revenues	18
9. Income Taxes	18
10. Benefit Plans	19
11. Derivative Instruments	20
12. Fair Value Measurements	21
13. Commitments and Contingencies	23
14. Segments of Business	25
15. Related Parties	26
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations	27
Item 3. Quantitative and Qualitative Disclosures About Market Risk	35
Item 4. Controls and Procedures	35
Part II. Other Information	35
Item 1. Legal Proceedings	35
Item 1A. Risk Factors	35
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds	35
Item 5. Other Information	35
Item 6. Exhibits	36
Signatures	36

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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 Alliant Energy’s, IPL’s or WPL’s 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 delivered 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, which could result from 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;

•the future development of technologies related to electrification, and the ability to reliably store and manage electricity;

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

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

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•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 process, or procure capacity in the market whereby such costs might not be recovered in rates;

•issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions permits and future changes in environmental laws and regulations, including changes to the Coal Combustion Residuals Rule, Cross-State Air Pollution Rule emissions allowances and federal, state or local regulations for greenhouse gases emissions reductions from new and existing fossil-fueled EGUs under the Clean Air Act, and litigation associated with environmental requirements;

•increased pressure from customers, investors and other stakeholders to more rapidly reduce greenhouse gases 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 and successful resolution of warranty issues or contract disputes 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;

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

•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		For the Six Months
	Ended June 30,		Ended June 30,
	2023	2022	2023	2022
	(in millions, except per share amounts)
Revenues:
Electric utility	$799	$812	$1,567	$1,586
Gas utility	77	94	353	356
Other utility	13	13	25	23
Non-utility	23	24	45	47
Total revenues	912	943	1,990	2,012
Operating expenses:
Electric production fuel and purchased power	166	191	322	359
Electric transmission service	138	133	284	271
Cost of gas sold	33	48	215	216
Other operation and maintenance	163	166	338	320
Depreciation and amortization	167	166	333	332
Taxes other than income taxes	28	27	59	54
Total operating expenses	695	731	1,551	1,552
Operating income	217	212	439	460
Other (income) and deductions:
Interest expense	96	78	190	152
Equity income from unconsolidated investments, net	(14)	(16)	(31)	(32)
Allowance for funds used during construction	(24)	(13)	(43)	(24)
Other	(1)	—	2	1
Total other (income) and deductions	57	49	118	97
Income before income taxes	160	163	321	363
Income tax expense (benefit)	—	4	(2)	12
Net income attributable to Alliant Energy common shareowners	$160	$159	$323	$351
Weighted average number of common shares outstanding:
Basic	251.7	250.9	251.4	250.7
Diluted	251.9	251.1	251.6	251.0
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)	$0.64	$0.63	$1.28	$1.40

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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ALLIANT ENERGY CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

	June 30, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$13	$20
Accounts receivable, less allowance for expected credit losses	428	516
Production fuel, at weighted average cost	64	53
Gas stored underground, at weighted average cost	69	132
Materials and supplies, at weighted average cost	172	140
Regulatory assets	196	166
Other	196	223
Total current assets	1,138	1,250
Property, plant and equipment, net	16,306	16,247
Investments:
ATC Holdings	372	358
Other	212	201
Total investments	584	559
Other assets:
Regulatory assets	2,148	1,880
Deferred charges and other	207	227
Total other assets	2,355	2,107
Total assets	$20,383	$20,163

LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt	$409	$408
Commercial paper	391	642
Other short-term borrowings	50	—
Accounts payable	585	756
Regulatory liabilities	121	206
Other	337	351
Total current liabilities	1,893	2,363
Long-term debt, net (excluding current portion)	8,186	7,668
Other liabilities:
Deferred tax liabilities	1,969	1,943
Regulatory liabilities	1,087	1,118
Pension and other benefit obligations	262	277
Other	534	518
Total other liabilities	3,852	3,856
Commitments and contingencies (Note 13)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 252,719,092 and 251,134,966 shares outstanding	3	3
Additional paid-in capital	2,854	2,777
Retained earnings	3,606	3,509
Accumulated other comprehensive income	3	—
Shares in deferred compensation trust - 405,051 and 402,134 shares at a weighted average cost of $33.69 and $32.63 per share	(14)	(13)
Total Alliant Energy Corporation common equity	6,452	6,276
Total liabilities and equity	$20,383	$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 Six Months
	Ended June 30,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$323	$351
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	333	332
Equity component of allowance for funds used during construction	(32)	(18)
Other	14	14
Other changes in assets and liabilities:
Accounts receivable	(186)	(283)
Gas stored underground	63	17
Derivative assets	86	(183)
Regulatory assets	(36)	(116)
Accounts payable	(84)	95
Derivative liabilities	18	86
Regulatory liabilities	(116)	74
Deferred income taxes	24	34
Other	(96)	(103)
Net cash flows from operating activities	311	300
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business	(758)	(550)
Other	(62)	(43)
Cash receipts on sold receivables	272	233
Proceeds from sales of partial ownership interest in West Riverside	120	—
Other	(54)	(10)
Net cash flows used for investing activities	(482)	(370)
Cash flows from financing activities:
Common stock dividends	(226)	(215)
Proceeds from issuance of common stock, net	76	13
Proceeds from issuance of long-term debt	862	650
Payments to retire long-term debt	(404)	(304)
Net change in commercial paper and other short-term borrowings	(146)	(116)
Contributions from noncontrolling interest	—	29
Other	(1)	(7)
Net cash flows from financing activities	161	50
Net decrease in cash, cash equivalents and restricted cash	(10)	(20)
Cash, cash equivalents and restricted cash at beginning of period	24	40
Cash, cash equivalents and restricted cash at end of period	$14	$20
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest	($179)	($146)
Income taxes, net	$3	($4)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$300	$200
Beneficial interest obtained in exchange for securitized accounts receivable	$175	$244

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		For the Six Months
	Ended June 30,		Ended June 30,
	2023	2022	2023	2022
	(in millions)
Revenues:
Electric utility	$431	$442	$819	$843
Gas utility	44	52	194	191
Steam and other	12	12	24	22
Total revenues	487	506	1,037	1,056
Operating expenses:
Electric production fuel and purchased power	66	83	113	150
Electric transmission service	96	91	201	188
Cost of gas sold	20	27	116	112
Other operation and maintenance	85	87	181	171
Depreciation and amortization	96	95	191	189
Taxes other than income taxes	14	14	29	28
Total operating expenses	377	397	831	838
Operating income	110	109	206	218
Other (income) and deductions:
Interest expense	37	37	74	74
Allowance for funds used during construction	(4)	(3)	(8)	(5)
Other	1	—	3	(1)
Total other (income) and deductions	34	34	69	68
Income before income taxes	76	75	137	150
Income tax benefit	(13)	(12)	(24)	(23)
Net income	$89	$87	$161	$173

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)

	June 30, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$9	$15
Accounts receivable, less allowance for expected credit losses	204	259
Production fuel, at weighted average cost	31	23
Gas stored underground, at weighted average cost	27	60
Materials and supplies, at weighted average cost	100	83
Regulatory assets	90	85
Other	78	93
Total current assets	539	618
Property, plant and equipment, net	7,923	8,046
Other assets:
Regulatory assets	1,558	1,301
Deferred charges and other	101	110
Total other assets	1,659	1,411
Total assets	$10,121	$10,075

LIABILITIES AND EQUITY
Current liabilities:
Accounts payable	$247	$239
Accounts payable to associated companies	40	28
Accrued taxes	51	52
Accrued interest	35	35
Regulatory liabilities	73	114
Other	97	113
Total current liabilities	543	581
Long-term debt, net	3,702	3,646
Other liabilities:
Deferred tax liabilities	1,061	1,047
Regulatory liabilities	603	640
Pension and other benefit obligations	60	62
Other	283	291
Total other liabilities	2,007	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	2,847	2,807
Retained earnings	989	968
Total Interstate Power and Light Company common equity	3,869	3,808
Total liabilities and equity	$10,121	$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 Six Months
	Ended June 30,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$161	$173
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	191	189
Other	2	(9)
Other changes in assets and liabilities:
Accounts receivable	(216)	(256)
Gas stored underground	33	12
Derivative assets	43	(123)
Regulatory assets	(2)	(52)
Accounts payable	(32)	67
Derivative liabilities	(9)	63
Regulatory liabilities	(78)	53
Deferred income taxes	8	24
Other	(49)	(58)
Net cash flows from operating activities	52	83
Cash flows from (used for) investing activities:
Construction and acquisition expenditures	(251)	(172)
Cash receipts on sold receivables	272	233
Other	(36)	(1)
Net cash flows from (used for) investing activities	(15)	60
Cash flows used for financing activities:
Common stock dividends	(140)	(160)
Capital contributions from parent	40	—
Net change in commercial paper	55	—
Other	2	(4)
Net cash flows used for financing activities	(43)	(164)
Net decrease in cash, cash equivalents and restricted cash	(6)	(21)
Cash, cash equivalents and restricted cash at beginning of period	15	34
Cash, cash equivalents and restricted cash at end of period	$9	$13
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest	($74)	($74)
Income taxes, net	$25	$19
Significant non-cash investing and financing activities:
Accrued capital expenditures	$95	$45
Beneficial interest obtained in exchange for securitized accounts receivable	$175	$244

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		For the Six Months
	Ended June 30,		Ended June 30,
	2023	2022	2023	2022
	(in millions)
Revenues:
Electric utility	$368	$370	$748	$743
Gas utility	33	42	159	165
Other	1	1	1	1
Total revenues	402	413	908	909
Operating expenses:
Electric production fuel and purchased power	99	108	209	209
Electric transmission service	42	41	83	83
Cost of gas sold	13	21	99	104
Other operation and maintenance	67	67	133	123
Depreciation and amortization	69	69	137	139
Taxes other than income taxes	13	12	27	24
Total operating expenses	303	318	688	682
Operating income	99	95	220	227
Other (income) and deductions:
Interest expense	36	28	72	55
Allowance for funds used during construction	(19)	(10)	(35)	(18)
Other	(4)	—	(3)	—
Total other (income) and deductions	13	18	34	37
Income before income taxes	86	77	186	190
Income tax expense	14	14	26	34
Net income	$72	$63	$160	$156

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)

	June 30, 2023	December 31, 2022
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$3	$5
Accounts receivable, less allowance for expected credit losses	210	244
Production fuel, at weighted average cost	33	29
Gas stored underground, at weighted average cost	42	73
Materials and supplies, at weighted average cost	70	54
Regulatory assets	106	81
Prepaid gross receipts tax	47	42
Other	47	60
Total current assets	558	588
Property, plant and equipment, net	7,882	7,722
Other assets:
Regulatory assets	590	579
Deferred charges and other	69	98
Total other assets	659	677
Total assets	$9,099	$8,987

LIABILITIES AND EQUITY
Current liabilities:
Commercial paper	$44	$290
Accounts payable	277	456
Regulatory liabilities	48	92
Other	140	111
Total current liabilities	509	949
Long-term debt, net	3,068	2,770
Other liabilities:
Deferred tax liabilities	785	789
Regulatory liabilities	484	478
Pension and other benefit obligations	127	140
Other	387	370
Total other liabilities	1,783	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	1,260	1,192
Total Wisconsin Power and Light Company common equity	3,739	3,491
Total liabilities and equity	$9,099	$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 Six Months
	Ended June 30,
	2023	2022
	(in millions)
Cash flows from operating activities:
Net income	$160	$156
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	137	139
Equity component of allowance for funds used during construction	(26)	(14)
Other	(4)	18
Other changes in assets and liabilities:
Accounts receivable	33	(17)
Gas stored underground	31	5
Derivative assets	47	(60)
Regulatory assets	(35)	(65)
Accounts payable	(54)	38
Derivative liabilities	27	23
Regulatory liabilities	(38)	20
Other	(10)	(45)
Net cash flows from operating activities	268	198
Cash flows used for investing activities:
Construction and acquisition expenditures	(507)	(378)
Proceeds from sales of partial ownership interest in West Riverside	120	—
Other	(15)	(6)
Net cash flows used for investing activities	(402)	(384)
Cash flows from financing activities:
Common stock dividends	(92)	(89)
Capital contributions from parent	180	265
Proceeds from issuance of long-term debt	297	—
Net change in commercial paper	(246)	(14)
Contributions from noncontrolling interest	—	29
Other	(7)	(3)
Net cash flows from financing activities	132	188
Net increase (decrease) in cash, cash equivalents and restricted cash	(2)	2
Cash, cash equivalents and restricted cash at beginning of period	5	2
Cash, cash equivalents and restricted cash at end of period	$3	$4
Supplemental cash flows information:
Cash paid during the period for:
Interest	($69)	($54)
Income taxes, net	($42)	($31)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$196	$150

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 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 six months ended June 30, 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 2. REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

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

	Alliant Energy		IPL		WPL
	June 30, 2023	December 31, 2022	June 30, 2023	December 31, 2022	June 30, 2023	December 31, 2022
Tax-related	$957	$929	$868	$848	$89	$81
Pension and OPEB costs	378	392	190	197	188	195
Assets retired early	290	70	274	53	16	17
Asset retirement obligations	197	151	156	110	41	41
Commodity cost recovery	145	160	6	1	139	159
Derivatives	102	84	41	48	61	36
IPL’s Duane Arnold Energy Center PPA amendment	54	66	54	66	—	—
WPL’s Western Wisconsin gas distribution expansion investments	47	48	—	—	47	48
Other	174	146	59	63	115	83
	$2,344	$2,046	$1,648	$1,386	$696	$660

Assets retired early - In May 2023, IPL retired the coal-fired Lansing Generating Station and reclassified the remaining net book value of this EGU from property, plant and equipment to a regulatory asset on Alliant Energy’s and IPL’s balance sheets. The related regulatory asset balance as of June 30, 2023 was $226 million, which is currently included in IPL’s rate base and IPL is earning a return of and a return on the remaining balance. Continued recovery of the remaining net book value of Lansing is expected to be addressed in future IPL rate reviews.

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the six months ended June 30, 2023, which resulted 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
	June 30, 2023	December 31, 2022	June 30, 2023	December 31, 2022	June 30, 2023	December 31, 2022
Tax-related	$572	$579	$301	$303	$271	$276
Cost of removal obligations	405	398	260	259	145	139
Derivatives	90	210	48	115	42	95
Commodity cost recovery	39	40	15	38	24	2
Electric transmission cost recovery	19	20	14	10	5	10
WPL’s West Riverside liquidated damages	17	32	—	—	17	32
Other	66	45	38	29	28	16
	$1,208	$1,324	$676	$754	$532	$570

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WPL’s West Riverside liquidated damages - Pursuant to PSCW authorization, WPL’s amortization of liquidated damages related to West Riverside construction procurement contracts was used to offset increases in WPL’s retail electric 2022/2023 Test Period revenue requirement, which resulted in decreases in regulatory liabilities on Alliant Energy’s and WPL’s balance sheets and decreases in depreciation and amortization expenses in Alliant Energy’s and WPL’s income statements for the three and six months ended June 30, 2023.

NOTE 3. PROPERTY, PLANT AND EQUIPMENT

In March 2023 and June 2023, Madison Gas and Electric Company and WEC Energy Group, Inc., respectively, acquired partial ownership interests in West Riverside. The related proceeds are included in “Proceeds from sales of partial ownership interest in West Riverside” in investing activities in Alliant Energy’s and WPL’s cash flows statements for the six months ended June 30, 2023. As a result of these transactions, WPL’s undivided current ownership interest in West Riverside is 73.8%.

NOTE 4. RECEIVABLES

NOTE 4(a) - Accounts Receivable - For the three and six months ended June 30, 2023, Alliant Energy’s, IPL’s and WPL’s gross write-offs for accounts receivable were as follows (in millions):

	Originated in 2022		Originated in 2023
	Three Months	Six Months	Three Months	Six Months
Alliant Energy	$3	$8	$2	$2
IPL	2	5	1	1
WPL	1	3	1	1

NOTE 4(b) - 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. In March 2023, IPL amended and extended through March 2024 the purchase commitment from the third party to which it sells its receivables. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of June 30, 2023, IPL had $50 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 and six months ended June 30 were as follows (in millions):

	Three Months		Six Months
	2023	2022	2023	2022
Maximum outstanding aggregate cash proceeds	$110	$66	$110	$66
Average outstanding aggregate cash proceeds	101	18	79	11

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2023	December 31, 2022
Customer accounts receivable	$148	$145
Unbilled utility revenues	100	132
Receivables sold to third party	248	277
Less: cash proceeds	60	80
Deferred proceeds	188	197
Less: allowance for expected credit losses	13	12
Fair value of deferred proceeds	$175	$185

As of June 30, 2023, outstanding receivables past due under the Receivables Agreement were $20 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months		Six Months
	2023	2022	2023	2022
Collections	$514	$500	$1,104	$1,061
Write-offs, net of recoveries	2	1	4	3

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NOTE 5. INVESTMENTS

Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):

	Three Months		Six Months
	2023	2022	2023	2022
ATC Holdings	($12)	($11)	($25)	($23)
Other	(2)	(5)	(6)	(9)
	($14)	($16)	($31)	($32)

NOTE 6. COMMON EQUITY

Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2023	251,134,966
At-the-market offering program	1,221,775
Shareowner Direct Plan	228,017
Equity-based compensation plans	134,334
Shares outstanding, June 30, 2023	252,719,092

At-the-Market Offering Program - In December 2022, Alliant Energy filed a prospectus supplement under which it may sell up to $225 million of its common stock through an at-the-market offering program. As of June 30, 2023, Alliant Energy issued 1,221,775 shares of common stock through this program and received cash proceeds of $64 million, net of $1 million in commissions and fees. Alliant Energy also had commitments not recognized on its balance sheet at June 30, 2023 to sell 172,701 shares of common stock under sales transactions executed through this program in late June 2023. Subsequent to June 30, 2023, Alliant Energy issued shares to settle these transactions in exchange for net cash proceeds of $9 million. The proceeds from the issuances of common stock were used for general corporate purposes.

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
				Accumulated	Shares in
		Additional		Other	Deferred
	Common	Paid-In	Retained	Comprehensive	Compensation	Noncontrolling	Total
	Stock	Capital	Earnings	Income (Loss)	Trust	Interest	Equity
Three Months Ended June 30, 2023
Beginning balance, March 31, 2023	$3	$2,780	$3,559	($1)	($13)	$—	$6,328
Net income attributable to Alliant Energy common shareowners			160				160
Common stock dividends ($0.4525 per share)