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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 September 30, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number 001-16189

NiSource Inc.

(Exact name of registrant as specified in its charter)


DE		35-2108964
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification No.)

801 East 86th Avenue
Merrillville,	IN	46410
(Address of principal executive offices)		(Zip Code)

(877) 647-5990

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:


Title of Each Class	Trading Symbol(s)	Name of Each Exchange on Which Registered
Common Stock, par value $0.01 per share	NI	NYSE

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.

Yes þ 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.)

Yes þ 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.

Large accelerated filer þ Accelerated filer ¨ Emerging growth company ☐ Non-accelerated filer ¨ Smaller reporting 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. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Yes ☐ No ☑

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date: Common Stock, $0.01 Par Value: 477,195,529 shares outstanding at October 22, 2025.

NISOURCE INC.

FORM 10-Q QUARTERLY REPORT

FOR THE QUARTER ENDED SEPTEMBER 30, 2025

Table of Contents


			Page

	Defined Terms		3

PART I	FINANCIAL INFORMATION

	Item 1.	Financial Statements - unaudited

		Condensed Statements of Consolidated Income (unaudited)	9

		Condensed Statements of Consolidated Comprehensive Income (unaudited)	10

		Condensed Consolidated Balance Sheets (unaudited)	11

		Condensed Statements of Consolidated Cash Flows (unaudited)	13

		Condensed Statements of Consolidated Equity (unaudited)	14

		Notes to Condensed Consolidated Financial Statements (unaudited)	17

	Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	43

	Item 3.	Quantitative and Qualitative Disclosures About Market Risk	67

	Item 4.	Controls and Procedures	67

PART II	OTHER INFORMATION

	Item 1.	Legal Proceedings	68

	Item 1A.	Risk Factors	68

	Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	71

	Item 3.	Defaults Upon Senior Securities	71

	Item 4.	Mine Safety Disclosures	71

	Item 5.	Other Information	71

	Item 6.	Exhibits	73

	Signature		74


DEFINED TERMS
The following is a list of frequently used abbreviations or acronyms that are found in this report:

NiSource Subsidiaries and Affiliates (not exhaustive)
Columbia of Kentucky			Columbia Gas of Kentucky, Inc.
Columbia of Maryland			Columbia Gas of Maryland, Inc.

Columbia of Ohio			Columbia Gas of Ohio, Inc.
Columbia of Pennsylvania			Columbia Gas of Pennsylvania, Inc.
Columbia of Virginia			Columbia Gas of Virginia, Inc.
GenCo			NIPSCO Generation LLC
Generation Holdings I			Generation Holdings I LLC
Generation Holdings II			Generation Holdings II LLC
NIPSCO			Northern Indiana Public Service Company LLC
NIPSCO Holdings I			NIPSCO Holdings I LLC
NIPSCO Holdings II			NIPSCO Holdings II LLC
NiSource ("we," "us" or "our")			NiSource Inc.
Rosewater			Rosewater Wind Generation LLC and its wholly owned subsidiary, Rosewater Wind Farm LLC
Indiana Crossroads Wind			Indiana Crossroads Wind Generation LLC and its wholly owned subsidiary, Indiana Crossroads Wind Farm LLC
Indiana Crossroads Solar			Indiana Crossroads Solar Generation LLC and its wholly owned subsidiary, Meadow Lake Solar Park LLC
Dunns Bridge I			Dunn's Bridge I Solar Generation LLC and its wholly owned subsidiary, Dunns Bridge Solar Center, LLC
Gibson			Gibson Solar LLC
Fairbanks			Fairbanks Solar Energy Center LLC


Abbreviations and Other

AFUDC			Allowance for funds used during construction

Amended LLC Agreement			Third Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II
AOCI			Accumulated Other Comprehensive Income (Loss)
ASC			Accounting Standards Codification
ASU			Accounting Standards Update
ATM			At-the-market
BIP			BIP Blue Buyer L.L.C
BIP Blue Buyer VCOC L.L.C			BIP Blue Buyer VCOC L.L.C., a Delaware limited liability company and also an affiliate of Blackstone
BIP Orion Holdco L.P.			BIP Orion Holdco L.P., a Delaware limited liability company and also an affiliate of Blackstone
BIP Orion Holdco II L.P.			BIP Orion Holdco II L.P., a Delaware limited liability company and also an affiliate of Blackstone
Blackstone			Blackstone Infrastructure Partners L.P.
BTA			Build-transfer agreement


Contract Assets			Generation assets and related transmission infrastructure to be developed in connection with the Data Center Contract
CCRs			Coal Combustion Residuals
CEP			Ohio Capital Expenditure Program
CERCLA			Comprehensive Environmental Response Compensation and Liability Act (also known as Superfund)


DEFINED TERMS
CODM			Chief Operating Decision Maker
Columbia Operations			Reportable segment comprised of the results of NiSource Gas Distribution company, including all of its Columbia Gas distribution companies and related subsidiaries
CPCN			Certificate of Public Convenience and Necessity




Customer			Purchaser of electricity under Data Center Contract, a wholly-owned subsidiary of a large publicly traded company
Data Center Contract			NIPSCO agreement to provide electricity to Customer’s data centers
DSIC			Distribution System Improvement Charge
DSM			Demand Side Management
Dunns Bridge II			Dunns Bridge II Solar Generation Center

EPA			United States Environmental Protection Agency
EPC			Engineering, procurement, and construction
EPS			Earnings per share
ERP			Enterprise Resource Planning
FAC			Fuel adjustment clause
FASB			Financial Accounting Standards Board

FMCA			Indiana Federally Mandated Cost Adjustment mechanism
GAAP			Generally Accepted Accounting Principles
GCA			Gas cost adjustment
Generation Assets			Power generations facilities and battery storage to be developed in connection with the Data Center Contract
GHG			Greenhouse gases
GWh			Gigawatt hours

IRA			Inflation Reduction Act of 2022
IRP			Ohio Infrastructure Replacement Program

IURC			Indiana Utility Regulatory Commission
Investor			BIP Orion Holdco L.P. and BIP Orion Holdco II L.P. in connection with Blackstone's GenCo minority equity investment
JV			Joint Venture

LIFO			Last In, First Out
LIHEAP			Low Income Heating Energy Assistance Program

LLC Agreement			Amended and Restated Limited Liability Company Agreement of Generation Holdings II
MGP			Manufactured Gas Plant
MISO			Midcontinent Independent System Operator
MMDth			Million dekatherms
MW			Megawatts
MWh			Megawatt hours

NIPSCO Electric			The electric generation and transmission activities of the NIPSCO Operations reportable segment
NIPSCO Gas			The gas distribution activities of the NIPSCO Operations reportable segment
NIPSCO Minority Interest Transaction			A transaction between NiSource, NIPSCO Holdings II (sole owner of NIPSCO) and an affiliate of Blackstone pursuant to a purchase and sale agreement entered into on June 17, 2023, that offered equity interests in NIPSCO Holdings II in exchange for capital contributions by the parties.
NIPSCO Operations			Reportable segment comprised of the results of NIPSCO Holdings I, NIPSCO Holdings II, and NIPSCO and all related subsidiaries


DEFINED TERMS
NYMEX			New York Mercantile Exchange

OPEB			Other Postemployment Benefits


PHMSA			Pipeline and Hazardous Materials Safety Administration
PPA			Power Purchase Agreement





RNG			Renewable Natural Gas

SAVE			Steps to Advance Virginia's Energy Plan
Scope 1 GHG Emissions			Direct emissions from sources owned or controlled by us (e.g., emissions from our combustion of fuel, vehicles, and process emissions and fugitive emissions)
Scope 2 GHG Emissions			Indirect emissions from sources owned or controlled by us
SEC			Securities and Exchange Commission

SMRP			Kentucky Safety Modification and Replacement Program
SMS			Safety Management System


TCJA			An Act to provide for reconciliation pursuant to titles II and V of the concurrent resolution on the budget for fiscal year 2018 (commonly known as the Tax Cuts and Jobs Act of 2017)
TDSIC			Indiana Transmission, Distribution and Storage System Improvement Charge
Templeton			Templeton Wind Energy Center


VIE			Variable Interest Entity
WAM			Work and Asset Management enterprise resourcing system

Note regarding forward-looking statements

This Quarterly Report on Form 10-Q contains "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Investors and prospective investors should understand that many factors govern whether any forward-looking statement contained herein will be or can be realized. Any one of those factors could cause actual results to differ materially from those projected. These forward-looking statements include, but are not limited to, statements concerning our plans, strategies, objectives, expected performance, expenditures, recovery of expenditures through rates, stated on either a consolidated or segment basis, and any and all underlying assumptions and other statements that are other than statements of historical fact. Expressions of future goals and expectations and similar expressions, including "may," "will," "should," "could," "would," "aims," "seeks," "expects," "plans," "anticipates," "intends," "believes," "estimates," "predicts," "potential," "targets," "forecast," and "continue," reflecting something other than historical fact are intended to identify forward-looking statements. All forward-looking statements are based on assumptions that management believes to be reasonable; however, there can be no assurance that actual results will not differ materially.

Factors that could cause actual results to differ materially from the projections, forecasts, estimates and expectations discussed in this Quarterly Report on Form 10-Q include, among other things:

•our ability to execute our business plan or growth strategy, including utility infrastructure investments, or business opportunities, such as data center development and related generation sources and transmission capabilities to meet potential load growth;

•our ability to manage data center growth in our service territories;

•potential incidents and other operating risks associated with our business;

•our ability to work successfully with our third-party investors;

•our ability to construct, develop and place into service the Contract Assets on time or at all and consistent with initial cost estimates, as well as the performance of these assets once constructed and placed into service;

•our ability to obtain the significant additional financing that will be required to construct the Contract Assets on favorable terms, if at all;

•our ability to recover our investments and realize our expected return under the Data Center Contract;

•our ability to maintain our investment grade credit ratings as we finance and pursue our data center strategy, including our performance under the Data Center Contract;

•our Customer’s performance under the Data Center Contract and any decision by the Customer to terminate the Data Center Contract or reduce the committed capacity thereunder;

•potential changes in the MISO accreditation treatment of capacity resources;

•our ability to adapt to, and manage costs related to, advances in technology, including alternative energy sources and changes in laws and regulations;

•our increased dependency on technology;

•impacts related to our aging infrastructure;

•our ability to obtain sufficient insurance coverage and whether such coverage will protect us against significant losses;

•the success of our electric generation strategy;

•construction risks and supply risks;

•fluctuations in demand from residential and commercial customers;

•fluctuations in the price of energy commodities and related transportation costs or an inability to obtain an adequate, reliable and cost-effective fuel supply to meet customer demand;

•our ability to attract, retain or re-skill a qualified, diverse workforce and maintain good labor relations;

•our ability to manage new initiatives and organizational changes;

•the performance and quality of third-party suppliers and service providers;

•our ability to manage the financial and operational risks related to achieving our carbon emission reduction goals, including our Net Zero Goal (as defined below), including any future associated impact from business opportunities such as data center development as those opportunities evolve;

•potential cybersecurity attacks or security breaches;

•increased requirements and costs related to cybersecurity;

•the actions of activist stockholders;

•any damage to our reputation;

•the impacts of natural disasters, potential terrorist attacks or other catastrophic events;

•the physical impacts of climate change and the transition to a lower carbon future;

•our debt obligations;

•any changes to our credit rating or the credit rating of certain of our subsidiaries;

•adverse economic and capital market conditions, including increases in inflation or interest rates, recession, or changes in investor sentiment;

•economic regulation and the impact of regulatory rate reviews;

•our ability to obtain expected financial or regulatory outcomes;

•economic conditions in certain industries;

•the reliability of customers and suppliers to fulfill their payment and contractual obligations;

•the ability of our subsidiaries to generate cash;

•pension funding obligations;

•potential impairments of goodwill;

•the outcome of legal and regulatory proceedings, investigations, incidents, claims and litigation;

•compliance with changes in, or new interpretations of applicable laws, regulations and tariffs, including impacts of state and federal orders on our ability to carry out our business plan and growth strategy;

•the cost of compliance with environmental laws and regulations and the costs of associated liabilities;

•changes in tax laws or the interpretation thereof;

•and other matters set forth in Part I, Item 2, “Management’s Discussion and Analysis of Financial Condition and Results of Operation,” and Part II, Item 1A, “Risk Factors,” of this report, and Part I, Item 1, “Business,” Part I, Item 1A, "Risk Factors," and Part II, Item 7, "Management’s Discussion and Analysis of Financial Condition and Results of Operations," of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, some of which risks are beyond our control.

In addition, the relative contributions to profitability by each business segment, and the assumptions underlying the forward-looking statements relating thereto, may change over time.

All forward-looking statements are expressly qualified in their entirety by the foregoing cautionary statements. We undertake no obligation to, and expressly disclaim any such obligation to, update or revise any forward-looking statements to reflect changed assumptions, the occurrence of anticipated or unanticipated events or changes to the future results over time or otherwise, except as required by law.


Index			Page
Condensed Statements of Consolidated Income (unaudited)			9
Condensed Statements of Consolidated Comprehensive Income (unaudited)			10
Condensed Consolidated Balance Sheets (unaudited)			11
Condensed Statements of Consolidated Cash Flows (unaudited)			13
Condensed Statements of Consolidated Equity (unaudited)			14
Notes to Condensed Consolidated Financial Statements (unaudited)			17
1. Basis of Accounting Presentation			17
2. Recent Accounting Pronouncements			17
3. Revenue Recognition			18
4. Noncontrolling Interests			22
5. Earnings Per Share			23


6. Equity			24
7. Short-Term Borrowings			25
8. Long-Term Debt			25

9. Regulatory Matters			26
10. Risk Management Activities			26
11. Fair Value			28

12. Income Taxes			31
13. Pension and Other Postemployment Benefits			32
14. Other Commitments and Contingencies			33
15. Accumulated Other Comprehensive Loss			36
16. Business Segment Information			37
17. Other, Net			40
18. Supplemental Disclosures of Cash Flow Information			41
19. Subsequent Event			42

Table of Contents

PART I

ITEM 1. FINANCIAL STATEMENTS

NiSource Inc.

Condensed Statements of Consolidated Income (unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions, except per share amounts)	2025		2024		2025		2024
Operating Revenues
Customer revenues	$	1,240.2	$	1,046.1	$	4,636.2	$	3,743.2
Other revenues	32.9		30.2		103.1		124.1
Total Operating Revenues	1,273.1		1,076.3		4,739.3		3,867.3
Operating Expenses
Cost of energy	193.6		165.9		1,102.9		755.6
Operation and maintenance	401.1		357.4		1,225.1		1,093.5
Depreciation and amortization	306.9		269.5		852.2		765.1
Loss on impairment of assets	—		—		0.7		2.9
Loss (gain) on sale of assets, net	(0.6)		(0.5)		0.2		1.1
Other taxes	74.6		65.7		238.4		210.4
Total Operating Expenses	975.6		858.0		3,419.5		2,828.6

Operating Income	297.5		218.3		1,319.8		1,038.7
Other Income (Deductions)
Interest expense, net	(179.8)		(134.6)		(451.7)		(380.2)
Other, net	9.9		29.2		16.2		51.4

Total Other Deductions, Net	(169.9)		(105.4)		(435.5)		(328.8)
Income before Income Taxes	127.6		112.9		884.3		709.9
Income Taxes	20.6		15.9		150.1		109.5


Net Income	107.0		97.0		734.2		600.4
Net income attributable to noncontrolling interest	12.3		11.3		62.5		63.9
Net Income Attributable to NiSource	94.7		85.7		671.7		536.5
Preferred dividends	—		—		—		(6.7)
Preferred redemption premium	—		—		—		(14.0)
Net Income Available to Common Shareholders	$	94.7	$	85.7	$	671.7	$	515.8
Earnings Per Share
Basic Earnings Per Share	$	0.20	$	0.19	$	1.42	$	1.15
Diluted Earnings Per Share	$	0.20	$	0.19	$	1.42	$	1.14
Basic Average Common Shares Outstanding	472.1		451.9		471.1		449.4
Diluted Average Common Shares	473.7		454.5		472.8		451.4

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Statements of Consolidated Comprehensive Income (unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions, net of taxes)	2025		2024		2025		2024
Net Income	$	107.0	$	97.0	$	734.2	$	600.4
Other comprehensive income:
Net unrealized gain on available-for-sale debt securities(1)	1.3		3.5		3.1		3.2
Reclassification adjustment for cash flow hedges(2)	(0.1)		(0.1)		(0.3)		(0.3)
Unrecognized pension and OPEB benefit(3)	14.0		0.6		14.6		1.1
Total other comprehensive income	15.2		4.0		17.4		4.0
Comprehensive Income	$	122.2	$	101.0	$	751.6	$	604.4

(1)Net unrealized gain on available-for-sale debt securities, net of $0.3 million tax expense and $0.9 million tax expense in the third quarter of 2025 and 2024, respectively, and $0.8 million tax expense for the nine months ended 2025 and 2024, respectively.

(2)Reclassification adjustment for cash flow hedges, net of $0.1 million tax benefit and $0.1 million tax benefit in the third quarter of 2025 and 2024, respectively, and $0.2 million tax benefit and $0.1 million tax benefit for the nine months ended 2025 and 2024, respectively.

(3)Unrecognized pension and OPEB benefit, net of $4.6 million tax expense and $0.2 million tax expense in the third quarter of 2025 and 2024, respectively, and $4.8 million tax expense and $0.4 million tax expense for the nine months ended 2025 and 2024, respectively.

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Consolidated Balance Sheets (unaudited)


(in millions)	September 30, 2025		December 31, 2024
ASSETS
Property, Plant and Equipment
Plant	$	37,201.7	$	34,152.9
Accumulated depreciation and amortization	(9,201.6)		(8,699.0)


Net Property, Plant and Equipment(1)	28,000.1		25,453.9
Investments and Other Assets
Unconsolidated affiliates	7.7		6.5
Available-for-sale debt securities (amortized cost of $160.4 and $91.9, allowance for credit losses of $0.1 and $0.1, respectively)	159.0		86.7
Other investments	116.2		85.5
Total Investments and Other Assets	282.9		178.7
Current Assets
Cash and cash equivalents	95.0		156.6
Restricted cash	24.5		42.0
Accounts receivable	719.6		987.9
Allowance for credit losses	(18.6)		(23.7)
Accounts receivable, net	701.0		964.2
Gas storage	268.3		179.6
Materials and supplies, at average cost	183.3		173.3
Electric production fuel, at average cost	23.7		36.2
Exchange gas receivable	42.9		45.7

Regulatory assets	326.5		319.9


Prepayments	157.4		138.5
Other current assets	25.6		24.2
Total Current Assets(1)	1,848.2		2,080.2
Other Assets
Regulatory assets	2,132.9		2,157.4
Goodwill	1,485.9		1,485.9

Deferred charges and other	652.9		432.0
Total Other Assets	4,271.7		4,075.3
Total Assets	$	34,402.9	$	31,788.1

(1)Includes $1,284.4 million and $1,323.8 million at September 30, 2025 and December 31, 2024, respectively, of net property, plant and equipment assets and $59.6 million and $65.0 million at September 30, 2025 and December 31, 2024, respectively, of current assets of consolidated VIEs that may be used only to settle obligations of the consolidated VIEs. Refer to Note 4, "Noncontrolling Interests," for additional information.

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Consolidated Balance Sheets (unaudited) (continued)


(in millions, except share amounts)	September 30, 2025		December 31, 2024
CAPITALIZATION AND LIABILITIES
Capitalization
Stockholders’ Equity
Common stock - $0.01 par value,750,000,000 shares authorized; 477,136,079 and 469,822,472 shares outstanding, respectively	$	4.8	$	4.7

Treasury stock	(99.9)		(99.9)
Additional paid-in capital	9,798.3		9,521.5
Retained deficit	(572.0)		(711.7)
Accumulated other comprehensive loss	(13.0)		(30.4)
Total NiSource Stockholders’ Equity	9,118.2		8,684.2
Noncontrolling interest in consolidated subsidiaries	2,123.6		1,984.1
Total Stockholders’ Equity	11,241.8		10,668.3
Long-term debt, excluding amounts due within one year	14,472.1		12,074.5
Total Capitalization	25,713.9		22,742.8
Current Liabilities
Current portion of long-term debt	31.3		1,281.2
Short-term borrowings	1,260.0		604.6
Accounts payable	712.0		863.1
Dividends payable - common stock	137.4		—

Customer deposits and credits	273.5		268.8
Taxes accrued	179.0		173.4
Interest accrued	198.2		157.0

Asset retirement obligations	66.3		84.6
Exchange gas payable	100.0		91.8


Regulatory liabilities	192.0		150.5
Accrued compensation and employee benefits	218.0		268.2


Other accruals	165.7		170.2
Total Current Liabilities(1)	3,533.4		4,113.4
Other Liabilities

Deferred income taxes	2,405.4		2,281.6


Accrued liability for postretirement and postemployment benefits	174.4		207.5
Regulatory liabilities	1,487.0		1,431.2
Asset retirement obligations	751.4		698.6
Other noncurrent liabilities and deferred credits	337.4		313.0
Total Other Liabilities(1)	5,155.6		4,931.9
Commitments and Contingencies (Refer to Note 14, "Other Commitments and Contingencies")
Total Capitalization and Liabilities	$	34,402.9	$	31,788.1

(1)Includes $54.4 million and $53.7 million at September 30, 2025 and December 31, 2024, respectively, of current liabilities and $55.0 million and $58.3 million at September 30, 2025 and December 31, 2024, respectively, of other liabilities, and finance leases of $40.2 million and $40.4 million at September 30, 2025 and December 31, 2024 respectively, of consolidated VIEs that creditors do not have recourse to our general credit. Refer to Note 4, "Noncontrolling Interests," for additional information.

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Statements of Consolidated Cash Flows (unaudited)


Nine Months Ended September 30, (in millions)	2025		2024
Operating Activities
Net Income	$	734.2	$	600.4
Adjustments to Reconcile Net Income to Net Cash from Operating Activities:

Depreciation and amortization	852.2		765.1
Deferred income taxes and investment tax credits	153.5		109.1
Loss on sale of assets	0.2		1.1


Payments for asset retirement obligations	(50.0)		(55.0)
Other adjustments	22.5		(14.9)
Changes in Assets and Liabilities:








Components of working capital(1)	(26.0)		(85.8)
Regulatory assets/liabilities	(19.5)		(35.6)


Deferred charges and other noncurrent assets	(24.4)		(45.1)
Other noncurrent liabilities and deferred credits	7.0		2.4
Net Cash Flows from Operating Activities	1,649.7		1,241.7
Investing Activities
Capital expenditures	(1,936.0)		(1,854.0)


Cost of removal	(113.8)		(108.9)


Milestone payments to renewable generation asset developers	(1,091.7)		(478.8)
Advanced deposits	(161.3)		—
Other investing activities	(93.8)		27.2
Net Cash Flows used for Investing Activities	(3,396.6)		(2,414.5)
Financing Activities
Proceeds from issuance of long-term debt	2,362.0		2,229.6
Repayments of finance lease obligations	(17.3)		(20.4)
Repayments of long-term debt	(1,250.0)		—

Repayment of short-term debt (maturity > 90 days)	—		(1,650.0)
Net change in commercial paper and other short-term borrowings	655.4		(1,141.6)
Issuance of common stock, net of issuance costs	259.1		507.9
Redemption of preferred stock	—		(486.1)
Preferred stock redemption premium	—		(14.0)
Equity costs, premiums and other debt related costs	(22.0)		(62.9)
Contributions from NIPSCO minority interest holders	145.3		99.5

Distribution to NIPSCO minority interest holders	(55.5)		(32.0)
Distributions to tax equity partners	(12.8)		(14.3)
Dividends paid - common stock	(396.4)		(357.0)
Dividends paid - preferred stock	—		(8.2)


Net Cash Flows from (used for) Financing Activities	1,667.8		(949.5)
Change in cash, cash equivalents and restricted cash	(79.1)		(2,122.3)
Cash, cash equivalents and restricted cash at beginning of period	198.6		2,281.1
Cash, Cash Equivalents and Restricted Cash at End of Period	$	119.5	$	158.8
(1) Refer to Note 18, "Supplemental Disclosures of Cash Flow Information," for additional information.

Reconciliation to Balance Sheet


Nine Months Ended September 30, (in millions)			2025
Cash and cash equivalents			95.0
Restricted cash			24.5
Total Cash, Cash Equivalents and Restricted Cash			119.5

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Statements of Consolidated Equity (unaudited)


(in millions)	Common Stock		Preferred Stock		Treasury Stock		Additional Paid-In Capital		Retained Deficit		Accumulated Other Comprehensive Loss		Noncontrolling Interest in Consolidated Subsidiaries		Total
Balance as of June 30, 2025	$	4.7	$	—	$	(99.9)	$	9,538.0	$	(532.1)	$	(28.2)	$	2,114.4	$	10,996.9
Comprehensive Income:
Net income	—		—		—		—		94.7		—		12.3		107.0
Other comprehensive income, net of tax	—		—		—		—		—		15.2		—		15.2
Dividends:
Common stock ($0.280 per share)	—		—		—		—		(134.6)		—		—		(134.6)

Noncontrolling Interests:
Contributions from noncontrolling interests	—		—		—		—		—		—		11.0		11.0
Distributions to noncontrolling interests	—		—		—		—		—		—		(14.1)		(14.1)

Stock issuances:




Employee stock purchase plan	—		—		—		1.9		—		—		—		1.9
Long-term incentive plan	—		—		—		7.2		—		—		—		7.2
401(k) and profit sharing	—		—		—		2.4		—		—		—		2.4
ATM program	0.1		—		—		248.8		—		—		—		248.9
Balance as of September 30, 2025	$	4.8	$	—	$	(99.9)	$	9,798.3	$	(572.0)	$	(13.0)	$	2,123.6	$	11,241.8


(in millions)	Common Stock		Preferred Stock		Treasury Stock		Additional Paid-In Capital		Retained Deficit		Accumulated Other Comprehensive Loss		Noncontrolling Interest in Consolidated Subsidiaries		Total
Balance as of December 31, 2024	$	4.7	$	—	$	(99.9)	$	9,521.5	$	(711.7)	$	(30.4)	$	1,984.1	$	10,668.3
Comprehensive Income:
Net income	—		—		—		—		671.7		—		62.5		734.2
Other comprehensive income, net of tax	—		—		—		—		—		17.4		—		17.4
Dividends:
Common stock ($1.120 per share)	—		—		—		—		(532.0)		—		—		(532.0)

Noncontrolling Interests:

Contributions from noncontrolling interests	—		—		—		—		—		—		145.3		145.3
Distributions to noncontrolling interests	—		—		—		—		—		—		(68.3)		(68.3)


Stock issuances:




Employee stock purchase plan	—		—		—		5.5		—		—		—		5.5
Long-term incentive plan	—		—		—		15.3		—		—		—		15.3
401(k) and profit sharing	—		—		—		7.2		—		—		—		7.2
ATM program	0.1		—		—		248.8		—		—		—		248.9
Balance as of September 30, 2025	$	4.8	$	—	$	(99.9)	$	9,798.3	$	(572.0)	$	(13.0)	$	2,123.6	$	11,241.8

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)


(in millions)	Common Stock		Preferred Stock		Treasury Stock		Additional Paid-In Capital		Retained Deficit		Accumulated Other Comprehensive Loss		Noncontrolling Interest in Consolidated Subsidiaries		Total
Balance as of June 30, 2024	$	4.5	$	—	$	(99.9)	$	8,894.2	$	(896.2)	$	(33.6)	$	1,950.6	$	9,819.6
Comprehensive Income:
Net income	—		—		—		—		85.7		—		11.3		97.0
Other comprehensive income, net of tax	—		—		—		—		—		4.0		—		4.0
Dividends:
Common stock ($0.265 per share)	—		—		—		—		(124.4)		—		—		(124.4)

Noncontrolling Interests:
Contributions from noncontrolling interests	—		—		—		—		—		—		39.8		39.8
Distributions to noncontrolling interest	—		—		—		—		—		—		(17.9)		(17.9)
Stock issuances:




Employee stock purchase plan	—		—		—		1.7		—		—		—		1.7
Long-term incentive plan	—		—		—		8.0		—		—		—		8.0
401(k) and profit sharing	—		—		—		2.2		—		—		—		2.2
ATM program	0.2		—		—		498.6		—		—		—		498.8
Balance as of September 30, 2024	$	4.7	$	—	$	(99.9)	$	9,404.7	$	(934.9)	$	(29.6)	$	1,983.8	$	10,328.8


(in millions)	Common Stock		Preferred Stock		Treasury Stock		Additional Paid-In Capital		Retained Deficit		Accumulated Other Comprehensive Loss		Noncontrolling Interest in Consolidated Subsidiaries		Total
Balance as of December 31, 2023	$	4.5	$	486.1	$	(99.9)	$	8,879.5	$	(967.0)	$	(33.6)	$	1,866.7	$	10,136.3
Comprehensive Income:
Net income	—		—		—		—		536.5		—		63.9		600.4
Other comprehensive income, net of tax	—		—		—		—		—		4.0		—		4.0
Dividends:
Common stock ($1.060 per share)	—		—		—		—		(482.3)		—		—		(482.3)
Preferred stock (See Note 6)	—		—		—		—		(8.1)		—		—		(8.1)

Noncontrolling Interests:
Contributions from noncontrolling interests	—		—		—		—		—		—		99.5		99.5
Distributions to noncontrolling interest	—		—		—		—		—		—		(46.3)		(46.3)
Stock issuances (redemptions):

Series B and B-1 Preferred stock redemption	—		(486.1)		—		—		—		—		—		(486.1)

Series B and B-1 Preferred stock redemption premium	—		—		—		—		(14.0)		—		—		(14.0)
Employee stock purchase plan	—		—		—		4.7		—		—		—		4.7
Long-term incentive plan	—		—		—		14.9		—		—		—		14.9
401(k) and profit sharing	—		—		—		7.0		—		—		—		7.0
ATM program	0.2		—		—		498.6		—		—		—		498.8
Balance as of September 30, 2024	$	4.7	$	—	$	(99.9)	$	9,404.7	$	(934.9)	$	(29.6)	$	1,983.8	$	10,328.8

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Condensed Statements of Consolidated Equity (unaudited) (continued)


	Preferred	Common
Shares (in thousands)	Shares	Shares	Treasury	Outstanding
Balance as of June 30, 2025	—	474,747	(3,963)	470,784
Issued:


Employee stock purchase plan	—	47	—	47
Long-term incentive plan	—	24	—	24
401(k) and profit sharing	—	55	—	55
ATM program	—	6,226	—	6,226


Balance as of September 30, 2025	—	481,099	(3,963)	477,136

	Preferred	Common
Shares (in thousands)	Shares	Shares	Treasury	Outstanding
Balance as of December 31, 2024	—	473,785	(3,963)	469,822
Issued:


Employee stock purchase plan	—	141	—	141
Long-term incentive plan	—	768	—	768
401(k) and profit sharing	—	179	—	179
ATM program	—	6,226	—	6,226


Balance as of September 30, 2025	—	481,099	(3,963)	477,136


	Preferred	Common
Shares (in thousands)	Shares	Shares	Treasury	Outstanding
Balance as of June 30, 2024	—	452,362	(3,963)	448,399
Issued:
Employee stock purchase plan	—	59	—	59
Long-term incentive plan	—	32	—	32
401(k) and profit sharing	—	69	—	69
ATM program	—	18,148	—	18,148


Balance as of September 30, 2024	—	470,670	(3,963)	466,707

	Preferred	Common
Shares (in thousands)	Shares	Shares	Treasury	Outstanding
Balance as of December 31, 2023	40	451,345	(3,963)	447,382
Issued:

Employee stock purchase plan	—	170	—	170
Long-term incentive plan	—	761	—	761
401(k) and profit sharing	—	246	—	246
ATM program	—	18,148	—	18,148
Redeemed:
Series B and B-1 Preferred Stock	(40)	—	—	—
Balance as of September 30, 2024	—	470,670	(3,963)	466,707

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.

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ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

1. Basis of Accounting Presentation

Our accompanying Condensed Consolidated Financial Statements (unaudited) reflect all normal recurring adjustments that are necessary, in the opinion of management, to present fairly the results of operations in accordance with GAAP in the United States of America. The accompanying financial statements include the accounts of us, our majority-owned subsidiaries, and VIEs of which we are the primary beneficiary after the elimination of all intercompany accounts and transactions.

The accompanying financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024. Income for interim periods may not be indicative of results for the calendar year due to weather variations and other factors.

The Condensed Consolidated Financial Statements (unaudited) have been prepared pursuant to the rules and regulations of the SEC. Certain information and note disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations, although we believe that the disclosures made in this Quarterly Report on Form 10-Q are adequate to make the information herein not misleading.

2. Recent Accounting Pronouncements

Recently Issued Accounting Pronouncements

In September 2025, the FASB issued ASU 2025-06, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. This pronouncement updates the guidance on capitalization of internal-use software, including removing the development stages utilized for evaluation of when certain activities are capital eligible. The ASU instead provides that an entity is required to start capitalizing eligible software development costs when (1) management has authorized and committed to funding the software project and (2) it is probable that the project will be completed and the software will be used to perform the function intended, which is referred to as the “probable-to-complete recognition threshold”. This probable-to-complete threshold includes an evaluation of whether there is significant uncertainty associated with the development activities of the software. The ASU is effective for fiscal years beginning after December 15, 2027. We are currently evaluating the impacts this amendment will have on our internal-use software capitalization policy.

In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40). This pronouncement requires disaggregated disclosure of income statement expenses for public business entities. The ASU requires disclosure in tabular format of disaggregation of relevant expense captions presented on the income statement by certain natural expense categories with certain related qualitative disclosures within the notes to the financial statements. The ASU does not change the expense captions an entity presents on the income statement. The ASU is effective for fiscal years beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027, as defined in ASU 2025-01, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40). We are currently evaluating the impacts this amendment will have on our required disclosures.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This pronouncement enhances required income tax disclosures. The pronouncement will require disclosure of specific categories and reconciling items included in the rate reconciliation, disaggregation between federal, state and local income taxes paid, and disclosure of income taxes paid by jurisdictions over a certain threshold. Additionally, the pronouncement eliminates certain required disclosures related to unrecognized tax benefits. This ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted, and is to be applied on a prospective basis with retrospective application permitted. We will implement and provide the required disclosures in our Annual Report on Form 10-K for the year ended December 31, 2025.

Recently Adopted Accounting Pronouncements

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This pronouncement enhances annual and interim disclosure requirements over reportable segments, primarily through enhanced disclosures about significant segment expenses. Specifically, the pronouncement requires disclosure of significant segment expenses that are regularly provided to the CODM and included within each reported measure of segment profit or loss, disclosure of an amount for other segment items representing the difference between segment revenue and segment expenses already disclosed, disclosure of all required annual disclosures for interim periods and disclosure of title and

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

position of the CODM and how the CODM uses reported measures. The pronouncement also allows for more than one measure of segment profit if the CODM uses more than one measure in assessing segment performance. This pronouncement was effective for annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. NiSource adopted this pronouncement as of December 31, 2024, with retrospective application and updated its disclosures to include significant expenses regularly provided to the CODM, the CODM's title and how the CODM utilizes reported measures. See Note 16, "Business Segment Information," for further discussion.

3. Revenue Recognition

Revenue Disaggregation and Reconciliation. We disaggregate revenue from contracts with customers based upon reportable segment, as well as by customer class. The Columbia Operations segment provides regulated natural gas service and transportation for residential, commercial and industrial customers in Ohio, Pennsylvania, Virginia, Kentucky, and Maryland. The NIPSCO Operations segment provides regulated gas and electric service in the northern part of Indiana.

The tables below reconcile revenue disaggregation by customer class to segment revenue, as well as to revenues reflected on the Condensed Statements of Consolidated Income (unaudited):

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)


Three months ended September 30, 2025 (in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Gas Distribution
Residential	$	328.1	$	72.9	$	—	$	401.0
Commercial	95.1		32.2		—		127.3
Industrial	36.0		19.7		—		55.7
Off-system	13.8		—		—		13.8


Miscellaneous(1)	6.7		2.6		—		9.3
Subtotal	$	479.7	$	127.4	$	—	$	607.1
Electric Generation and Power Delivery
Residential	$	—	$	254.6	$	—	$	254.6
Commercial	—		210.6		—		210.6
Industrial	—		156.2		—		156.2
Wholesale	—		18.4		—		18.4

Miscellaneous(1)	—		(6.7)		—		(6.7)
Subtotal	$	—	$	633.1	$	—	$	633.1
Total Customer Revenues(2)	479.7		760.5		—		1,240.2
Other Revenues(3)	5.2		26.5		1.2		32.9
Total Operating Revenues	$	484.9	$	787.0	$	1.2	$	1,273.1
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations primarily relate to late fees and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets. Amounts included in Corporate and Other primarily relate to products and services revenue.

Three months ended September 30, 2024 (in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Gas Distribution
Residential	$	296.9	$	66.8	$	—	$	363.7
Commercial	78.3		28.6		—		106.9
Industrial	32.0		16.4		—		48.4
Off-system	7.1		—		—		7.1
Wholesale	0.1		—		—		0.1

Miscellaneous(1)	2.9		1.9		—		4.8
Subtotal	$	417.3	$	113.7	$	—	$	531.0
Electric Generation and Power Delivery
Residential	$	—	$	197.9	$	—	$	197.9
Commercial	—		172.7		—		172.7
Industrial	—		124.8		—		124.8

Wholesale	—		15.0		—		15.0
Public Authority	—		2.0		—		2.0
Miscellaneous(1)	—		2.7		—		2.7
Subtotal	$	—	$	515.1	$	—	$	515.1
Total Customer Revenues(2)	417.3		628.8		—		1,046.1
Other Revenues(3)	6.1		23.8		0.3		30.2
Total Operating Revenues	$	423.4	$	652.6	$	0.3	$	1,076.3
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations, primarily relate to revenue refunds, public repairs and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)


Nine months ended September 30, 2025 (in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Gas Distribution
Residential	$	1,576.3	$	478.5	$	—	$	2,054.8
Commercial	527.8		180.8		—		$	708.6
Industrial	121.5		73.7		—		$	195.2
Off-system	58.9		—		—		$	58.9


Miscellaneous(1)	27.4		10.6		—		$	38.0
Subtotal	$	2,311.9	$	743.6	$	—	$	3,055.5
Electric Generation and Power Delivery
Residential	$	—	$	586.4	$	—	$	586.4
Commercial	—		531.7		—		$	531.7
Industrial	—		432.3		—		$	432.3
Wholesale	—		37.9		—		$	37.9

Miscellaneous(1)	—		(7.6)		—		$	(7.6)
Subtotal	$	—	$	1,580.7	$	—	$	1,580.7
Total Customer Revenues(2)	2,311.9		2,324.3		—		4,636.2
Other Revenues(3)	14.8		84.7		3.6		103.1
Total Operating Revenues	$	2,326.7	$	2,409.0	$	3.6	$	4,739.3
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations primarily relate to late fees and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets. Amounts included in Corporate and Other primarily relate to products and services revenue.

Nine months ended September 30, 2024 (in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Gas Distribution
Residential	$	1,257.2	$	357.5	$	—	$	1,614.7
Commercial	395.6		134.0		—		$	529.6
Industrial	105.1		56.3		—		$	161.4
Off-system	30.5		—		—		$	30.5
Wholesale	1.1		—		—		$	1.1

Miscellaneous(1)	15.4		12.5		—		$	27.9
Subtotal	$	1,804.9	$	560.3	$	—	$	2,365.2
Electric Generation and Power Delivery
Residential	$	—	$	498.6	$	—	$	498.6
Commercial	—		470.0		—		$	470.0
Industrial	—		360.4		—		$	360.4

Wholesale	—		32.4		—		$	32.4
Public Authority	—		6.0		—		$	6.0
Miscellaneous(1)	—		10.6		—		$	10.6
Subtotal	$	—	$	1,378.0	$	—	$	1,378.0
Total Customer Revenues(2)	1,804.9		1,938.3		—		3,743.2
Other Revenues(3)	59.6		63.9		0.6		124.1
Total Operating Revenues	$	1,864.5	$	2,002.2	$	0.6	$	3,867.3
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations, primarily relate to revenue refunds, public repairs and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Customer Accounts Receivable. Accounts receivable on our Condensed Consolidated Balance Sheets (unaudited) includes both billed and unbilled amounts, as well as certain amounts that are not related to customer revenues. Unbilled amounts of accounts receivable relate to a portion of a customer’s consumption of gas or electricity from the date of the last cycle billing through the last day of the month (balance sheet date). Factors taken into consideration when estimating unbilled revenue include historical usage, customer rates, and weather. A significant portion of our operations are subject to seasonal fluctuations in sales. During the heating season, primarily from November through March, revenues and receivables from gas sales are more significant than in other months. The balances of customer receivables as of September 30, 2025 and December 31, 2024 are presented in the table below. We had no significant contract assets or liabilities during the period. Additionally, we have not incurred any significant costs to obtain or fulfill contracts.


(in millions)	Customer Accounts Receivable, Billed (less reserve)		Customer Accounts Receivable, Unbilled (less reserve)
Balance as of December 31, 2024	$	525.1	$	408.1
Balance as of September 30, 2025	$	444.6	$	219.5

Utility revenues are billed to customers monthly on a cycle basis. We expect that substantially all customer accounts receivable will be collected following customer billing, as this revenue consists primarily of periodic, tariff-based billings for service and usage. We maintain common utility credit risk mitigation practices, including requiring deposits and actively pursuing collection of past due amounts. Our regulated operations also utilize certain regulatory mechanisms that facilitate recovery of bad debt costs within tariff-based rates, which provides further evidence of collectibility. It is probable that substantially all of the consideration to which we are entitled from customers will be collected upon satisfaction of performance obligations.

Allowance for Credit Losses. To evaluate for expected credit losses, customer account receivables are pooled based on similar risk characteristics, such as customer type, geography, payment terms, and related macro-economic risks. Expected credit losses are established using a model that considers historical collections experience, current information, and reasonable and supportable forecasts. Internal and external inputs are used in our credit model including, but not limited to, energy consumption trends, revenue projections, actual charge-offs data, recoveries data, shut-offs, customer delinquencies, final bill data, and inflation. We continuously evaluate available information relevant to assessing collectability of current and future receivables. We evaluate creditworthiness of specific customers periodically or following changes in facts and circumstances. When we become aware of a specific commercial or industrial customer's inability to pay, an allowance for expected credit losses is recorded for the relevant amount. We also monitor other circumstances that could affect our overall expected credit losses including, but not limited to, creditworthiness of overall population in service territories, adverse conditions impacting an industry sector, and current economic conditions.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

At each reporting period, we record expected credit losses to an allowance for credit losses account. When deemed to be uncollectible, customer accounts are written-off. A rollforward of our allowance for credit losses as of September 30, 2025 and December 31, 2024 are presented in the table below:


(in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Balance as of December 31, 2024	$	9.8	$	13.9	$	—	$	23.7
Current period provisions	26.2		10.2		—		36.4
Write-offs charged against allowance	(39.7)		(9.2)		—		(48.9)
Recoveries of amounts previously written off	6.7		0.7		—		7.4
Balance as of September 30, 2025	$	3.0	$	15.6	$	—	$	18.6


(in millions)	Columbia Operations		NIPSCO Operations		Corporate and Other		Total
Balance as of December 31, 2023	$	10.2	$	11.9	$	0.8	$	22.9
Current period provisions	26.7		12.1		—		38.8
Write-offs charged against allowance	(43.9)		(11.0)		(0.8)		(55.7)
Recoveries of amounts previously written off	16.8		0.9		—		17.7
Balance as of December 31, 2024	$	9.8	$	13.9	$	—	$	23.7

4. Noncontrolling Interests

Variable Interest Entities. A VIE is an entity in which the controlling interest is determined through means other than a majority voting interest. NIPSCO is the managing member and operator of two wind JVs, Rosewater and Indiana Crossroads Wind, which have 102 MW and 302 MW of nameplate capacity, respectively. NIPSCO is also the managing member and operator of two solar JVs, Indiana Crossroads Solar and Dunns Bridge I, which have a nameplate capacity of 200 MW and 265 MW, respectively. We have determined that these JVs are VIEs. NIPSCO controls decisions that are significant to these entities' ongoing operations and economic results. Therefore, we have concluded that NIPSCO is the primary beneficiary and have consolidated all four entities.

Members of each respective JV include NIPSCO (who is the managing member) and a tax equity partner. Earnings, tax attributes and cash flows are allocated to both NIPSCO and the tax equity partner in varying percentages by category and over the life of the partnership. NIPSCO and each tax equity partner contributed cash to the respective JV. Once the tax equity partner has earned their negotiated rate of return and have reached a stated contractual date, NIPSCO has the option to purchase the remaining interest in the respective JV, at fair market value, from the tax equity partner. NIPSCO has an obligation to purchase 100% of the electricity generated by each commercially operational JV.

We did not provide any financial or other support during the quarter that was not contractually required.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Our Condensed Consolidated Balance Sheets (unaudited) included the following assets and liabilities associated with VIEs.


(in millions)	September 30, 2025		December 31, 2024
Net property, plant and equipment	$	1,284.4	$	1,323.8
Current assets	59.6		65.0

Total assets(1)	1,344.0		1,388.8
Current liabilities	54.4		53.7
Asset retirement obligations	55.0		58.3
Finance lease obligations	40.2		40.4
Total liabilities(1)(2)	$	149.6	$	152.4

(1)The assets of each consolidated VIE can only be used to settle obligations of the respective consolidated VIE. The creditors of the liabilities of the VIEs do not have recourse to the general credit of the primary beneficiary.
(2)In addition to the amounts disclosed above there is a de minimis amount of other noncurrent assets and liabilities at Rosewater as of September 30, 2025.

Voting Interest Entities. We retain a controlling financial interest in NIPSCO Holdings II and its subsidiaries and consolidate their financial results. The following table provides information about the contributions from and distributions to our NIPSCO minority interest holders included in our Condensed Statements of Consolidated Cash Flows (unaudited) and Condensed Statements of Consolidated Equity (unaudited).


	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions)	2025		2024		2025		2024
Contributions from NIPSCO minority interest holders	$	11.0	$	39.8	$	145.3	$	99.5
Distributions to NIPSCO minority interest holders	11.1		11.8		55.5		32.0

5. Earnings Per Share

The calculations of basic and diluted EPS are based on the weighted average number of shares of common stock and potential common stock outstanding during the period. Diluted EPS includes the incremental effects of the various long-term incentive compensation plans and ATM forward sale agreements under the treasury stock method when the impact would be dilutive (See Note 6, "Equity").

We use the two-class method of computing earnings per share because we have participating securities in the form of non-vested restricted stock units with a non-forfeitable right to dividend equivalents, for which vesting is predicated solely on the passage of time. The calculation of earnings per share using the two-class method excludes income attributable to these participating securities from the numerator and excludes the dilutive impact of those shares from the denominator.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The following table presents the calculation of our basic and diluted EPS:


	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions, except per share amounts)	2025		2024		2025		2024
Numerator:
Net Income Available to Common Shareholders	$	94.7	$	85.7	$	671.7	$	515.8
Less: Income allocated to participating securities	0.3		0.2		1.4		0.9
Net Income Available to Common Shareholders - Basic	94.4		85.5		670.3		514.9

Net Income Available to Common Shareholders - Diluted	$	94.4	$	85.5	$	670.3	$	514.9
Denominator:
Average common shares outstanding - Basic	472.1		451.9		471.1		449.4
Dilutive potential common shares:


Shares contingently issuable under employee stock plans	1.0		0.9		1.1		0.9
Shares restricted under employee stock plans	0.4		0.3		0.5		0.3
ATM forward sale agreements	0.2		1.4		0.1		0.8
Average Common Shares - Diluted	473.7		454.5		472.8		451.4
Earnings per common share:
Basic	$	0.20	$	0.19	1.42		1.15
Diluted	$	0.20	$	0.19	1.42		1.14

6. Equity

ATM Program. In February 2024, we entered into eight separate equity distribution agreements pursuant to which we are able to sell up to an aggregate of $900.0 million of our common stock.

In February 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,000,000 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $40.10 per share. In September 2025, we settled the forward sale agreement in shares for $80.0 million, based on a net price of $40.02 per share.

In March 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 1,707,320 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $41.00 per share. In September 2025, we settled the forward sale agreement in shares for $69.9 million, based on a net price of $40.92 per share.

In June 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,518,393 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $39.71 per share. In September 2025, we settled the forward sale agreement in shares for $99.1 million, based on a net price of $39.36 per share.

As of September 30, 2025, the ATM program had approximately $47.5 million of capacity available. The program expires on December 31, 2025.

Series B and B-1 Preferred Stock. On March 15, 2024, we redeemed all 20,000 outstanding shares of Series B Preferred Stock for a redemption price of $25,000 per share and all 20,000 outstanding shares of Series B-1 Preferred Stock for a redemption price of $0.01 per share or $500.0 million in total.

There were no dividends declared per share for the Series B Preferred Stock during the three months ended September 30, 2025 and 2024. Dividends declared per share for the Series B Preferred Stock were zero and $406.25 during the nine months ended September 30, 2025 and 2024, respectively.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

7. Short-Term Borrowings

We generate short-term borrowings from our revolving credit facility, commercial paper program, and accounts receivable transfer programs. Each of these borrowing sources is described further below.

Revolving Credit Facility. We maintain a revolving credit facility to fund ongoing working capital requirements, including the provision of liquidity support for our commercial paper program, the issuance of letters of credit and general corporate purposes. Our revolving credit facility has a program limit of $1.85 billion and is comprised of a syndicate of banks. We had no outstanding borrowings under this facility as of September 30, 2025 and December 31, 2024.

Commercial Paper Program. Our commercial paper program has a program limit of $1.85 billion. We had $1,060.0 million and $604.6 million of commercial paper outstanding with weighted-average interest rates of 4.40% and 4.73% as of September 30, 2025 and December 31, 2024, respectively.

Accounts Receivable Transfer Programs. Columbia of Ohio, NIPSCO, and Columbia of Pennsylvania each maintain a receivables agreement whereby they transfer their customer accounts receivables to third-party financial institutions through consolidated special purpose entities. The three agreements expire between May 2026 and October 2026 and may be further extended if mutually agreed to by the parties thereto.

All receivables transferred to third parties are valued at face value, which approximates fair value due to their short-term nature. The amount of the undivided percentage ownership interest in the accounts receivables transferred is determined in part by required loss reserves under the agreements.

Transfers of accounts receivable are accounted for as secured borrowings resulting in the recognition of short-term borrowings on the Condensed Consolidated Balance Sheets (unaudited). As of September 30, 2025, the maximum amount of debt that could be borrowed related to our accounts receivable programs was $245.0 million.

We had $200.0 million and no short-term borrowings related to the securitization transactions as of September 30, 2025 and December 31, 2024, respectively.

For the nine months ended September 30, 2025 and 2024, $200.0 million and $(337.6) million, respectively, were recorded as cash flows from (used for) financing activities related to the change in short-term borrowings due to securitization transactions. Columbia of Ohio, NIPSCO and Columbia of Pennsylvania remain responsible for collecting on the receivables securitized, and the receivables cannot be transferred to another party.

Items listed above are presented net in the Condensed Statements of Consolidated Cash Flows (unaudited) as their maturities are less than 90 days.

8. Long-Term Debt

On March 27, 2025, we completed the issuance and sale of $750.0 million of 5.850% senior unsecured notes maturing in 2055, which resulted in approximately $739.6 million of net proceeds after discount and debt issuance costs.

On June 27, 2025, we completed the issuance and sale of an additional $750.0 million of 5.850% senior unsecured notes maturing in 2055 (the "2055 Notes"). The terms of the 2055 Notes, other than the issue date and the price to the public, are identical to the terms of, and constitute a reopening of, our 5.850% senior unsecured notes maturing in 2055 issued on March 27, 2025. With the incremental issuance, we now have $1.5 billion of 5.850% senior unsecured notes maturing in 2055. On June 27, 2025, we also completed the issuance and sale of $900.0 million of 5.350% senior unsecured notes maturing in 2035 (the "2035 Notes"). The issuances of the additional 2055 Notes and the 2035 Notes in June 2025 resulted in approximately $1.616 billion of total net proceeds after discount and debt issuance costs.

On August 15, 2025, we repaid $1,250.0 million of 0.95% senior unsecured notes at maturity.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

9. Regulatory Matters

Regulatory Assets and Liabilities. We follow the accounting and reporting requirements of ASC Topic 980, which provides that regulated entities account for and report assets and liabilities consistent with the economic effect of regulatory rate-making procedures when the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates will be charged and collected from customers. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income or expense are deferred on the balance sheet and are recognized in the income statement as the related amounts are included in customer rates and recovered from or refunded to customers. We assess the probability of collection for all of our regulatory assets each period. The offset to the regulatory liability associated with our renewable investments included in regulated rates is recorded in "Depreciation and amortization" on the Condensed Statements of Consolidated Income (unaudited).

Renewable generation filings. In February 2025, NIPSCO filed a petition with the IURC to modify its February 2023 order that approved a power purchase agreement related to Templeton and allow for NIPSCO to fully own Templeton. The IURC issued an order on September 24, 2025 approving the filed petition.

GenCo filing. In January 2025, GenCo, an indirect subsidiary of NiSource Inc., filed a declination of jurisdiction petition with the IURC related to the ownership, development, financing, construction and operation of generation facilities. This is an administrative filing and is a step in NIPSCO’s effort to set up a framework to accommodate megaload customers, including data centers. A settlement agreement among GenCo, NIPSCO, and a coalition of NIPSCO's largest industrial customers was approved by the IURC on September 24, 2025. In October 2025, the Indiana Office of the Utility Consumer Counselor ("OUCC") filed a limited Request for Rehearing with the IURC. Subsequently, the OUCC filed a Notice of Appeal of the IURC order approving the GenCo settlement, which was immediately stayed by the Court of Appeals to allow the IURC process to be completed.

NIPSCO Electric rate case filing. On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC. The IURC issued an order on June 26, 2025, approving the Settlement Agreement without modification. New rates were implemented in multiple steps beginning in July 2025 and will continue with the final step no later than March 2026.

10. Risk Management Activities

We are exposed to certain risks relating to our ongoing business operations; namely commodity price risk and interest rate risk. We recognize that the prudent and selective use of derivatives may help to limit volatility in the price of natural gas and manage interest rate exposure.

Risk management assets and liabilities on our derivatives are presented on the Condensed Consolidated Balance Sheets (unaudited) as shown below:


	September 30, 2025				December 31, 2024
(in millions)	Assets		Liabilities		Assets		Liabilities
Current(1)

Derivatives not designated as hedging instruments	$	10.5	$	2.8	$	9.1	$	2.3
Total	$	10.5	$	2.8	$	9.1	$	2.3
Noncurrent(2)

Derivatives not designated as hedging instruments	$	12.8	$	3.7	$	17.9	$	1.2
Total	$	12.8	$	3.7	$	17.9	$	1.2

(1)Current assets and liabilities are presented in "Other current assets" and "Other accruals", respectively, on the Condensed Consolidated Balance Sheets (unaudited).

(2)Noncurrent assets and liabilities are presented in "Deferred charges and other" and "Other noncurrent liabilities and deferred credits", respectively, on the Condensed Consolidated Balance Sheets (unaudited).

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Our derivative instruments are subject to enforceable master netting arrangements or similar agreements. No collateral was either received or posted related to our outstanding derivative positions at September 30, 2025. If the above gross asset and liability positions were presented net of amounts owed or receivable from counterparties, we would report a net asset position of $16.8 million and $23.5 million at September 30, 2025 and December 31, 2024, respectively.

Derivatives Not Designated as Hedging Instruments

Commodity price risk management. We, along with our utility customers, are exposed to variability in cash flows associated with natural gas purchases and volatility in natural gas prices. We purchase natural gas for sale and delivery to our retail, commercial and industrial customers, and for most customers the variability in the market price of gas is passed through in their rates. Some of our utility subsidiaries offer programs whereby variability in the market price of gas is assumed by the respective utility. The objective of our commodity price risk programs is to mitigate the gas cost variability on behalf of our customers associated with natural gas purchases or sales by economically hedging the various gas cost components using a combination of futures, options, forwards or other derivative contracts. At September 30, 2025 and December 31, 2024, we had 89.4 MMDth and 77.8 MMDth, respectively, of net energy derivative volumes outstanding related to our natural gas hedges.

NIPSCO has received approval for a program to lock in a fixed price for its natural gas customers using long-term forward purchase instruments and is limited to 20% of NIPSCO's average annual GCA purchase volume. As of September 30, 2025, the remaining terms of these instruments range from one to seven years. Likewise, Columbia of Pennsylvania has received approval for a 24-month rolling hedge program that will continue in perpetuity. The program is designed to financially hedge approximately 20% of the customers' annual demand. Under both programs all gains and losses on these derivative contracts are deferred as regulatory liabilities or assets and are remitted to or collected from customers through the relevant cost recovery mechanism.

The following table summarizes the gains and losses associated with the commodity price risk programs deferred as regulatory assets and liabilities:


(in millions)	September 30, 2025		December 31, 2024
Regulatory Assets
Losses on commodity price risk programs	$	10.9	$	6.5
Regulatory Liabilities
Gains on commodity price risk programs	23.8		28.7

Our derivative instruments measured at fair value as of September 30, 2025 and December 31, 2024 do not contain any credit-risk-related contingent features.

Derivatives Designated as Hedging Instruments

Interest rate risk management. As of September 30, 2025 and December 31, 2024 we had no active interest rate swap positions. We have recorded the overall net loss related to previously settled interest rate swaps in AOCI. The gain or loss associated with each previously settled interest rate swap is amortized in interest expense over the term of each corresponding debt issuance. These amounts were immaterial for the three and nine months ended September 30, 2025 and 2024 and are recorded in "Interest expense, net" on the Condensed Statements of Consolidated Income (unaudited). Amounts expected to be reclassified to earnings during the next twelve months are immaterial. See Note 15, "Accumulated Other Comprehensive Loss," for additional information.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

11. Fair Value

A. Fair Value Measurements

Recurring Fair Value Measurements

The following tables present financial assets and liabilities measured and recorded at fair value on our Condensed Consolidated Balance Sheets (unaudited) on a recurring basis and their level within the fair value hierarchy as of September 30, 2025 and December 31, 2024. As of September 30, 2025 and December 31, 2024, there were no material transfers between fair value hierarchies. Additionally, there were no changes in the method or significant assumptions used to estimate the fair value of our financial instruments.


Recurring Fair Value Measurements September 30, 2025 (in millions)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance as of September 30, 2025
Assets

U.S. Treasury debt securities(1)	$	4.0	$	—	$	—	$	4.0
Risk management assets	—		23.3		—		23.3

Available-for-sale debt securities	—		159.0		—		159.0
Equity securities(2)(3)	$	8.5	$	—	$	—	$	8.5
Total	$	12.5	$	182.3	$	—	$	194.8
Liabilities

Risk management liabilities	$	—	$	6.5	$	—	$	6.5
Total	$	—	$	6.5	$	—	$	6.5

(1)Treasury bills are presented in "Cash and cash equivalents" and "Restricted cash" on the Consolidated Balance Sheets.

(2)Equity securities are in a high dividend equity fund and are valued using market prices in active markets. Level 1 instrument valuations are obtained from real-time quotes for transactions in active exchange markets involving identical assets. Equity securities are presented in "Other Investments" on the Consolidated Balance Sheets.

(3)As of September 30, 2025, the investment cost of equity securities measured at fair value was $7.9 million, gross unrealized gains were $0.6 million, and the fair value was $8.5 million.


Recurring Fair Value Measurements December 31, 2024 (in millions)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance as of December 31, 2024
Assets


U.S. Treasury debt securities(1)	$	80.1	$	—	$	—	$	80.1
Risk management assets	—		27.0		—		27.0


Available-for-sale debt securities	—		86.7		—		86.7
Total	$	80.1	$	113.7	$	—	$	193.8
Liabilities

Risk management liabilities	$	—	$	3.5	$	—	$	3.5
Total	$	—	$	3.5	$	—	$	3.5

(1)Treasury bills are presented in "Cash and cash equivalents" and "Restricted cash" on the Consolidated Balance Sheets.

Level 1- When utilized, exchange-traded derivative contracts are based on unadjusted quoted prices in active markets and are classified within Level 1. These financial assets and liabilities are secured with cash on deposit with the exchange; therefore, nonperformance risk has not been incorporated into these valuations. These financial assets and liabilities are deemed to be cleared and settled daily by NYMEX as the related cash collateral is posted with the exchange. As a result of this exchange rule, NYMEX derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes, and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and are subject to future commodity price fluctuations until they are settled in accordance with their contractual terms.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Level 2- Certain non-exchange-traded derivatives are valued using broker or over-the-counter, on-line exchanges. In such cases, these non-exchange-traded derivatives are classified within Level 2. Non-exchange-based derivative instruments include swaps, forwards, and options. In certain instances, these instruments may utilize models to measure fair value taking into consideration credit risk. We use a similar model to value similar instruments. Valuation models utilize various inputs that include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, other observable inputs for the asset or liability and market-corroborated inputs, (i.e., inputs derived principally from or corroborated by observable market data by correlation or other means). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized within Level 2.

Level 3- Certain derivatives trade in less active markets with a lower availability of pricing information and models may be utilized in the valuation. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized within Level 3.

Risk Management Assets and Liabilities. Risk management assets and liabilities include exchange-traded NYMEX futures and NYMEX options and non-exchange-based forward purchase contracts. NIPSCO and Columbia of Pennsylvania have entered into long-term forward natural gas purchase instruments to lock in a fixed price for natural gas customers. We value these contracts using a pricing model that incorporates market-based information when available, as these instruments trade less frequently and are classified within Level 2 of the fair value hierarchy. For additional information, see Note 10, "Risk Management Activities."

Available-for-Sale Debt Securities. Available-for-sale debt securities are investments pledged as collateral for trust accounts related to our wholly owned insurance company. We value U.S. Treasury, corporate debt and mortgage-backed securities using a matrix pricing model that incorporates market-based information. These securities trade less frequently and are classified within Level 2.

Our available-for-sale debt securities impairments are recognized periodically using an allowance approach. At each reporting date, we utilize a quantitative and qualitative review process to assess the impairment of available-for-sale debt securities at the individual security level. For securities in a loss position, we evaluate our intent to sell or whether it is more-likely-than-not that we will be required to sell the security prior to the recovery of its amortized cost. If either criteria is met, the loss is recognized in earnings immediately, with the offsetting entry to the carrying value of the security. If both criteria are not met, we perform an analysis to determine whether the unrealized loss is related to credit factors. The analysis focuses on a variety of factors that include, but are not limited to, downgrade on ratings of the security, defaults in the current reporting period or projected defaults in the future, the security's yield spread over treasuries, and other relevant market data. If the unrealized loss is not related to credit factors, it is included in other comprehensive income. If the unrealized loss is related to credit factors, the loss is recognized as credit loss expense in earnings during the period, with an offsetting entry to the allowance for credit losses. The amount of the credit loss recorded to the allowance account is limited by the amount at which the security's fair value is less than its amortized cost basis. If certain amounts recorded in the allowance for credit losses are deemed uncollectible, the allowance on the uncollectible portion will be charged off, with an offsetting entry to the carrying value of the security. Subsequent improvements to the estimated credit losses of available-for-sale debt securities will be recognized immediately in earnings. Continuous credit monitoring and portfolio credit balancing mitigates our risk of credit losses on our available-for-sale debt securities.

The amortized cost, gross unrealized gains and losses, allowance for credit losses, and fair value of available-for-sale securities at September 30, 2025 and December 31, 2024 were:


September 30, 2025 (in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses(1)		Allowance for Credit Losses		Fair Value
Available-for-sale debt securities
U.S. Treasury debt securities	10.6		$	—	$	—	$	—	$	10.6
Corporate/Other debt securities	$	149.8	$	2.3	$	(3.6)	$	(0.1)	$	148.4
Total	$	160.4	$	2.3	$	(3.6)	$	(0.1)	$	159.0

December 31, 2024 (in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses(2)		Allowance for Credit Losses		Fair Value
Available-for-sale debt securities

Corporate/Other debt securities	$	91.9	$	0.5	$	(5.6)	$	(0.1)	$	86.7
Total	$	91.9	$	0.5	$	(5.6)	$	(0.1)	$	86.7

(1)Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $1.5 million and $55.9 million at September 30, 2025.

(2)Fair value of Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $70.1 million at December 31, 2024.

The cost of maturities sold is based upon specific identification. Net realized gains and losses on available-for-sale securities were de minimis and $0.1 million for the three and nine months ended September 30, 2025, respectively, and $0.1 million and $0.5 million for the three and nine months ended September 30, 2024.

Equity Investments. Investments measured at net asset value per share (or its equivalent) as a practical expedient have not been classified in the fair value hierarchy. These investments represent holdings in a single private investment fund that are redeemable at the election of the holder. As of September 30, 2025, the Company holds $17.9 million of equity investments measured at net asset value.

Non-recurring Fair Value Measurements

We measure the fair value of certain assets, primarily goodwill, on a non-recurring basis, typically when events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable.

B. Other Fair Value Disclosures for Financial Instruments. The carrying amount of cash and cash equivalents, restricted cash, notes receivable, customer deposits and short-term borrowings is a reasonable estimate of fair value due to their liquid or short-term nature. Our long-term borrowings are recorded at historical amounts.

The following method and assumptions were used to estimate the fair value of each class of financial instruments.

Long-term Debt. The fair value of outstanding long-term debt is estimated based on the quoted market prices for the same or similar securities. Certain premium costs associated with the early settlement of long-term debt are not taken into consideration in determining fair value. These fair value measurements are classified within Level 2 of the fair value hierarchy. As of September 30, 2025, there was no change in the method or significant assumptions used to estimate the fair value of long-term debt.

The carrying amount and estimated fair values of these financial instruments were as follows:


(in millions)	Carrying Amount as of September 30, 2025		Estimated Fair Value as of September 30, 2025		Carrying Amount as of Dec. 31, 2024		Estimated Fair Value as of Dec. 31, 2024
Long-term debt (including current portion)	$	14,503.4	$	14,050.3	$	13,355.7	$	12,505.2

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

12. Income Taxes

Our interim effective tax rates reflect the estimated annual effective tax rates for 2025 and 2024 applied to year-to-date pretax income, adjusted for tax expense associated with certain discrete items. The effective tax rates for the three months ended September 30, 2025 and 2024 were 16.1% and 14.1%, respectively. The effective tax rates for the nine months ended September 30, 2025 and 2024 were 17.0% and 15.4%, respectively. These effective tax rates differ from the federal statutory tax rate of 21% primarily due to net income attributable to noncontrolling interest, amortization of excess deferred income taxes, federal tax credits net of deferred regulatory liabilities, state income taxes, and other permanent book-to-tax differences.

The increase in the three month effective tax rate of 2.0% in 2025 compared to 2024 is primarily driven by changes in net income attributable to noncontrolling interest, lower AFUDC equity and increases to other permanent differences, partially offset by lower state income taxes.

The increase in the nine month effective tax rate of 1.6% in 2025 compared to 2024 is primarily driven by lower AFUDC equity and changes in net income attributable to noncontrolling interest.

As of September 30, 2025, there have been no material changes to our unrecognized tax benefits or possible changes that could reasonably be expected to occur during the next twelve months. See Note 15 to the Company’s Consolidated Financial Statements in the Annual Report on Form 10-K for the year ended December 31, 2024, for a discussion of these unrecognized tax benefits.

On July 4, 2025, President Donald J. Trump enacted the One Big Beautiful Bill Act ("OBBBA"), which introduced significant federal tax and spending reforms. After evaluation, management determined that the OBBBA does not currently have a material effect on the Company’s financial statements. The Company will continue to monitor the bill’s implementation and will update its financial disclosures as needed should material impacts arise under applicable accounting standards.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

13. Pension and Other Postemployment Benefits

We provide defined contribution plans and noncontributory defined benefit retirement plans that cover certain of our employees. Benefits under the defined benefit retirement plans reflect the employees' compensation, years of service and age at retirement. Additionally, we provide health care and life insurance benefits for certain retired employees. Certain active employees may become eligible for these benefits if they reach retirement age while working for us. The expected cost of such benefits is accrued during the employees' years of service. We determined that, for certain rate-regulated subsidiaries, the future recovery of postretirement benefit costs is probable, and we record regulatory assets and liabilities for amounts that would otherwise have been recorded to expense or accumulated other comprehensive loss. Current rates of rate-regulated companies include postretirement benefit costs, including amortization of the regulatory assets and liabilities that arose prior to inclusion of these costs in rates. For most plans, cash contributions are remitted to grantor trusts.

For the nine months ended September 30, 2025 and 2024, we contributed $1.5 million and $1.9 million, respectively, to our pension plans and $15.4 million and $18.3 million, respectively, to our OPEB plans.

The following table provides the components of the plans' actuarially determined net periodic benefit cost for the three and nine months ended September 30, 2025 and 2024:


	Pension Benefits				OPEB
Three Months Ended September 30, (in millions)	2025		2024		2025		2024
Components of Net Periodic Benefit Cost(1)
Service cost	$	4.9	$	5.5	$	1.0	$	1.3
Interest cost	16.0		16.3		5.6		5.5
Expected return on assets	(23.1)		(23.8)		(4.2)		(4.0)
Amortization of prior service credit	—		—		(0.4)		(0.4)
Recognized actuarial loss	6.4		7.2		0.4		0.8
Settlement loss	5.6		5.9		—		—
Total Net Periodic Benefit Cost	$	9.8	$	11.1	$	2.4	$	3.2
(1)The service cost component and all non-service cost components of net periodic benefit (income) cost are presented in "Operation and maintenance" and "Other, net," respectively, on the Condensed Statements of Consolidated Income (unaudited).


	Pension Benefits				OPEB
Nine Months Ended September 30, (in millions)	2025		2024		2025		2024
Components of Net Periodic Benefit Cost(1)
Service cost	$	14.7	$	16.4	$	3.0	$	3.9
Interest cost	48.0		48.9		16.8		16.4
Expected return on assets	(69.3)		(71.4)		(12.6)		(12.0)
Amortization of prior service credit	—		—		(1.2)		(1.2)
Recognized actuarial loss	19.2		21.6		1.2		2.4
Settlement loss	5.6		5.9		—		—
Total Net Periodic Benefit Cost	$	18.2	$	21.4	$	7.2	$	9.5
(1)The service cost component and all non-service cost components of net periodic benefit (income) cost are presented in "Operation and maintenance" and "Other, net," respectively, on the Condensed Statements of Consolidated Income (unaudited).

During the three months ended September 30, 2025, one of our qualified pension plans met the requirement for settlement accounting. A one-time settlement charge of $5.6 million was recorded during the three months ended September 30, 2025.

In August 2025, we communicated to plan participants of one of our OPEB plans the intention to move from a group self-insured Medicare supplemental health plan to a Sponsored Health Reimbursement Account, with eligible retirees electing coverage through a Healthcare Exchange. This change will become effective on January 1, 2026. Given the intention of the plan and communication to participants, this was considered a plan amendment at the time of communication. This plan amendment triggered remeasurement of this plan, resulting in a decrease to the OPEB regulatory asset of $5.7 million, a decrease to OPEB

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

liability of $23.3 million, and an increase to accumulated other comprehensive loss of $17.6 million. Net periodic OPEB benefit cost for 2025 decreased by $1.7 million as a result of the interim remeasurement.

In line with the remeasurement, key inputs, economic assumptions, and demographic assumptions changed to calculate the updated OPEB benefit obligation and the net periodic benefit cost at the interim remeasurement date for the plan that triggered settlement accounting. For remeasurement, we used a weighted-average discount rate of 5.53%, a weighted-average health care trend rate of 9.97% for next year and ultimate trend rate of 4.75% to be reached in 2034, and weighted-average expected return on assets of 6.88%.

14. Other Commitments and Contingencies

A. Guarantees and Indemnities. We and certain of our subsidiaries enter into various agreements providing financial or performance assurance to third parties on behalf of certain subsidiaries as a part of normal business. Such agreements include guarantees and stand-by letters of credit. These agreements are entered into primarily to support or enhance the creditworthiness otherwise attributed to a subsidiary on a stand-alone basis, thereby facilitating the extension of sufficient credit to accomplish the subsidiaries' intended commercial purposes. As of September 30, 2025 and December 31, 2024, we had issued letters of credit of $119.0 million and $9.4 million, respectively, for the benefit of third parties.

We provide guarantees related to our future performance under BTAs for our renewable generation projects. At September 30, 2025 and December 31, 2024, our guarantees for multiple BTAs totaled $29.2 million and $1,127.5 million, respectively. The amount of each guaranty will decrease upon the substantial completion of the construction of the facilities. See ''- D. Other Matters - Generation Transition,'' below for more information.

We provide guarantees related to some of our rail and pipeline service agreements. As of September 30, 2025 and December 31, 2024, if we do not meet our contractual obligations under the terms of these agreements we would be required to pay up to a maximum of $52.0 million and $61.7 million, respectively.

B. Legal Proceedings. From time to time, various legal and regulatory claims and proceedings are pending or threatened against the Company and its subsidiaries. While the amounts claimed may be substantial, the Company is unable to predict with certainty the ultimate outcome of such claims and proceedings. The Company establishes reserves whenever it believes it to be appropriate for pending litigation matters. However, the actual results of resolving the pending litigation matters may be substantially higher than the amounts reserved. If one or more matters were decided against us, the effects could be material to our results of operations in the period in which we would be required to record or adjust the related liability and could also be material to our cash flows in the periods that we would be required to pay such liability. Due to the inherent uncertainty of litigation, there can be no assurance that the resolution of any particular claim, proceeding or investigation would not have a material adverse effect on our results of operations, financial position or liquidity.

Other Claims and Proceedings. We are also party to other claims, regulatory and legal proceedings arising in the ordinary course of business in each state in which we have operations, and based upon an investigation of these matters and discussion with legal counsel, we believe the ultimate outcome of such other legal proceedings to be individually, or in aggregate, not material at this time.

C. Environmental Matters. Our operations are subject to environmental statutes and regulations related to air quality, water quality, hazardous waste and solid waste. We believe that we are in substantial compliance with the environmental regulations currently applicable to our operations.

It is management's continued intent to address environmental issues in cooperation with regulatory authorities in such a manner as to achieve mutually acceptable compliance plans. However, there can be no assurance that fines and penalties will not be incurred. Management expects a majority of environmental assessment and remediation costs and asset retirement costs, further described below, to be recoverable through rates.

As of September 30, 2025 and December 31, 2024, we had recorded a liability of $84.6 million and $91.8 million, respectively, to cover environmental remediation at various sites. This liability is included in "Other accruals" and "Other noncurrent liabilities and deferred credits" in the Condensed Consolidated Balance Sheets (unaudited). We recognize costs associated with environmental remediation obligations when the incurrence of such costs is probable and the amounts can be reasonably estimated. The original estimates for remediation activities may differ materially from the amount ultimately expended. The actual future expenditures depend on many factors, including laws and regulations, the nature and extent of impact and the

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

method of remediation. These expenditures are not currently estimable at some sites. We periodically adjust our liability as information is collected and estimates become more refined.

CERCLA. Our subsidiaries are potentially responsible parties at waste disposal sites under CERCLA and similar state laws. Under CERCLA, each potentially responsible party can be held jointly, severally and strictly liable for the remediation costs as the EPA, or state, can allow the parties to pay for remedial action or perform remedial action themselves and request reimbursement from the potentially responsible parties. Our affiliates have retained CERCLA environmental liabilities, including remediation liabilities, associated with certain current and former operations. At this time, we cannot estimate the full cost of remediating properties that have not yet been investigated, but it is possible that the future costs could be material to the Condensed Consolidated Financial Statements (unaudited).

MGP. We maintain a program to identify and investigate former MGP sites where our subsidiaries or predecessors may have liability. The program has identified 51 such sites where liability is probable. Remedial actions at many of these sites are being overseen by state or federal environmental agencies through consent agreements or voluntary remediation agreements.

We utilize a probabilistic model to estimate our future remediation costs related to MGP sites. The model was prepared with the assistance of a third party and incorporates our experience and general industry experience with remediating MGP sites. We perform an annual update of the model in the second quarter each year. No material changes to the estimated future remediation costs were identified during the update completed as of June 30, 2025. Our total estimated liability related to the facilities subject to remediation was $77.3 million and $86.4 million at September 30, 2025 and December 31, 2024, respectively. The liability represents our best estimate of the probable cost to remediate the MGP sites. Our model indicates that it is reasonably possible that remediation costs could vary by as much as $16.5 million and $16.3 million at September 30, 2025 and December 31, 2024, respectively, in addition to the costs noted above. Remediation costs are estimated based on the best available information, applicable remediation standards at the balance sheet date and experience with similar facilities.

CCRs. NIPSCO continues to meet the compliance requirements established by the EPA for the regulation of CCRs. The CCR rule requirements currently in effect required revisions to previously recorded legal obligations associated with the retirement of certain NIPSCO facilities. The actual asset retirement costs related to the CCR rule may vary substantially from the estimates used to record the increased asset retirement obligation due to the uncertainty about the requirements that will be established by environmental authorities, compliance strategies that will be used, and the preliminary nature of available data used to estimate costs. As allowed by the rule, NIPSCO will continue to collect data over time to determine the specific compliance solutions and associated costs and, as a result, the actual costs may vary.

On May 8, 2024, the EPA finalized changes to the current CCR regulations ("Legacy CCR Rule"), which address inactive surface impoundments at inactive facilities, referred to as legacy impoundments, and CCR management units ("CCRMUs") at inactive and active facilities. The rule largely requires these newly regulated units to conform to existing requirements, such as groundwater monitoring, closure requirements, and post-closure care. In the second quarter of 2025, we accrued an additional $38.8 million to cover probable and estimable compliance activities associated with the Legacy CCR Rule. NIPSCO continues to assess whether existing legal obligations associated with the retirement of certain facilities must be revised and to estimate probable additional required asset retirement costs. NIPSCO expects to receive recovery of any such costs through existing and future depreciation rates.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

D. Other Matters.

Generation Transition. NIPSCO has executed several BTAs with developers to construct renewable generation facilities. In October 2024, NIPSCO contracted with a developer to convert the previously approved Templeton PPA to a BTA and in February 2025 filed a CPCN with the IURC seeking approval of the full ownership BTA structure. In September 2025, the IURC granted NIPSCO a CPCN to acquire Templeton through the full ownership BTA structure. NIPSCO's purchase obligation under Templeton is dependent on timely completion of construction. Certain agreements require NIPSCO to make partial payments upon the developer's completion of significant construction milestones.

In January 2025, the Fairbanks project achieved mechanical completion, resulting in NIPSCO making a $336.6 million payment to the developer. In May 2025, the Fairbanks project achieved substantial completion, resulting in NIPSCO making a $141.4 million payment to the developer in June 2025.

In January 2025, the Dunns Bridge II project achieved substantial completion, resulting in NIPSCO making a $217.6 million payment to the developer in February 2025.

In June 2025, the Gibson project achieved mechanical completion, resulting in NIPSCO making a $262.4 million payment to the developer. In August 2025, the Gibson project achieved substantial completion, resulting in NIPSCO making a $133.7 million payment to the developer in September 2025.

EPC Agreements. GenCo has entered into certain EPC contracts to construct generation capacity assets to support the Data Center Contract, requiring payments at specified periods. The assets contemplated by these contracts are subject to IURC approval. We may terminate for convenience the EPC Contracts and pay certain incurred project costs and termination fees if the Data Center Contract is terminated or IURC approval of the underlying assets is not obtained.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

15. Accumulated Other Comprehensive Loss

The following tables display the components of Accumulated Other Comprehensive Loss, net of tax:


(in millions)	Gains and Losses on Securities(1)		Gains and Losses on Cash Flow Hedges(1)		Pension and OPEB Items(1)		Accumulated Other Comprehensive Loss(1)
Balance as of June 30, 2025	$	(2.2)	$	(13.4)	$	(12.6)	$	(28.2)
Other comprehensive income before reclassifications	1.3		—		13.8		15.1
Amounts reclassified from accumulated other comprehensive loss	—		(0.1)		0.2		0.1
Net current-period other comprehensive income (loss)	1.3		(0.1)		14.0		15.2

Balance as of September 30, 2025	$	(0.9)	$	(13.5)	$	1.4	$	(13.0)
(1)All amounts are net of tax. Amounts in parentheses indicate debits.
(in millions)	Gains and Losses on Securities(1)		Gains and Losses on Cash Flow Hedges(1)		Pension and OPEB Items(1)		Accumulated Other Comprehensive Loss(1)
Balance as of December 31, 2024	$	(4.0)	$	(13.2)	$	(13.2)	$	(30.4)
Other comprehensive income before reclassifications	3.1		—		13.9		17.0
Amounts reclassified from accumulated other comprehensive loss	—		(0.3)		0.7		0.4
Net current-period other comprehensive income (loss)	3.1		(0.3)		14.6		17.4

Balance as of September 30, 2025	$	(0.9)	$	(13.5)	$	1.4	$	(13.0)

(1)All amounts are net of tax. Amounts in parentheses indicate debits.


(in millions)	Gains and Losses on Securities(1)		Gains and Losses on Cash Flow Hedges(1)		Pension and OPEB Items(1)		Accumulated Other Comprehensive Loss(1)
Balance as of June 30, 2024	$	(7.6)	$	(13.0)	$	(13.0)	$	(33.6)
Other comprehensive income (loss) before reclassifications	3.5		0.4		(0.1)		3.8
Amounts reclassified from accumulated other comprehensive loss	—		(0.5)		0.7		0.2
Net current-period other comprehensive income (loss)	3.5		(0.1)		0.6		4.0

Balance as of September 30, 2024	$	(4.1)	$	(13.1)	$	(12.4)	$	(29.6)
(1)All amounts are net of tax. Amounts in parentheses indicate debits.
(in millions)	Gains and Losses on Securities(1)		Gains and Losses on Cash Flow Hedges(1)		Pension and OPEB Items(1)		Accumulated Other Comprehensive Loss(1)
Balance as of December 31, 2023	$	(7.3)	$	(12.8)	$	(13.5)	$	(33.6)
Other comprehensive income (loss) before reclassifications	2.8		—		(0.1)		2.7
Amounts reclassified from accumulated other comprehensive loss	0.4		(0.3)		1.2		1.3
Net current-period other comprehensive income (loss)	3.2		(0.3)		1.1		4.0

Balance as of September 30, 2024	$	(4.1)	$	(13.1)	$	(12.4)	$	(29.6)

(1)All amounts are net of tax. Amounts in parentheses indicate debits.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

16. Business Segment Information

Our reportable segments reflect the manner in which our business is managed and our resources are allocated. Our operations are divided into two primary reportable segments, the Columbia Operations and the NIPSCO Operations segments. Columbia Operations aggregates the results of the fully regulated and wholly owned subsidiaries of NiSource Gas Distribution Group, Inc. (a holding company that owns Columbia of Kentucky, Columbia of Maryland, Columbia of Ohio, Columbia of Pennsylvania, and Columbia of Virginia). Each Columbia distribution company is an operating segment which we aggregate to form the Columbia Operations reportable segment. NIPSCO Operations includes the results of NIPSCO Holdings I and its majority-owned subsidiaries, including NIPSCO, which has regulated gas and electric operations in northern Indiana.

The remainder of our operations, which are not significant enough on a stand-alone basis to warrant treatment as a reportable segment, are presented as "Corporate and Other" and primarily are comprised of interest expense on holding company debt and unallocated corporate costs and activities. Refer to Note 3, "Revenue Recognition," for additional information on our segments and their sources of revenues. The following table provides information about our reportable segments. We use operating income as the primary measurement of performance for each of the reportable segments and make decisions on financing, dividends and taxes at the corporate level on a consolidated basis. We provide this measure to our CODM, the CEO, who utilizes it to assess performance and allocation of resources at the operating segment level based on budget-to-actual and actual-to-actual variances. Segment revenues include intersegment sales to affiliated subsidiaries, which are eliminated in consolidation. Affiliated sales are recognized on the basis of prevailing market, regulated prices or at levels provided for under contractual agreements. Operating income is derived from revenues and expenses directly associated with each segment.


Three Months Ended September 30, 2025
(in millions)	Columbia Operations		NIPSCO Operations		Total of Reportable Segments
Operating Revenues
External Revenue	$	484.9	$	787.0	$	1,271.9
Intersegment Revenue	3.3		0.3		3.6
Total Operating Revenue	$	488.2	$	787.3	$	1,275.5

Cost of energy	58.5		135.2		193.7
O&M	212.8		215.1		427.9
Depreciation	112.7		185.3		298.0
Total other taxes	52.0		19.1		71.1
Other segment items(1)	0.1		—		0.1




Operating Income	$	52.1	$	232.6	$	284.7

(1)Other segment items consists of Loss on Sale or Impairment of Assets and other segment income or expenses deemed insignificant which are used to reach our measurement of segment profit or loss, Operating Income.

Table of Contents

ITEM 1. FINANCIAL STATEMENTS (continued)

NiSource Inc.

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)


Three Months Ended September 30, 2024
(in millions)	Columbia Operations		NIPSCO Operations		Total of Reportable Segments
Operating Revenues
External Revenue	$	423.4	$	652.6	$	1,076.0
Intersegment Revenue	3.3		0.3		3.6
Total Operating Revenue	426.7		652.9		1,079.6

Cost of energy	34.2		131.7		165.9
O&M	202.9		177.7		380.6
Depreciation	103.0		156.8		259.8

Total other taxes	45.4		15.4		60.8





Operating Income	$	41.2	$	171.3	$	212.5


Nine Months Ended September 30, 2025
(in millions)	Columbia Operations		NIPSCO Operations		Total of Reportable Segments
Operating Revenues
External Revenue	$	2,326.7	$	2,409.0	$	4,735.7
Intersegment Revenue	10.0		0.8		10.8
Total Operating Revenue	$	2,336.7	$	2,409.8	$	4,746.5

Cost of energy	548.7		554.3		1,103.0
O&M	663.5		628.1		1,291.6
Depreciation	332.6		492.5		825.1
Total other taxes	171.4		55.7		227.1
Other segment items(1)	0.4		0.7		1.1

NISOURCE INC. 10-Q