NISOURCE INC. (NI)

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

NiSource Inc.

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NiSource Inc.

EXECUTIVE SUMMARY

This Management's Discussion and Analysis of Financial Condition and Results of Operations ("Management’s Discussion") includes management’s analysis of past financial results and certain potential factors that may affect future results, potential future risks and approaches that may be used to manage those risks. See "Note regarding forward-looking statements" at the beginning of this report for a list of factors that may cause results to differ materially.

Management's Discussion is designed to provide an understanding of our operations and financial performance and should be read in conjunction with our Condensed Consolidated Financial Statements (unaudited) included in this report and our Annual Report on Form 10-K for the fiscal year ended December 31, 2025.

We are an energy holding company under the Public Utility Holding Company Act of 2005 whose primary subsidiaries are fully regulated natural gas and electric utility companies serving customers in six states. We generate substantially all of our operating income through these rate-regulated businesses, which are summarized for financial reporting purposes into two primary reportable segments: Columbia Operations and NIPSCO Operations. Refer to ''Note 15, "Business Segment Information," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for further discussion of our business segments.

Our vision is to be a premier, innovative and trusted energy partner. We exist to deliver safe, reliable and competitive energy that drives value to our customers. In order to achieve this goal, we seek to develop strategies that benefit all stakeholders as we (i) support long-term infrastructure investment and safety programs to better serve our customers, (ii) align our tariff structures and regulatory programs with our cost structure, and (iii) create value and enable growth in an evolving energy ecosystem. These strategies focus on improving safety and reliability, enhancing customer experience, pursuing regulatory and legislative initiatives to increase accessibility for customers currently not on our gas and electric service, ensuring customer value and reducing emissions while generating sustainable returns. The safety of our customers, communities and employees remains our focus. Serving as a guiding practice for our SMS, NiSource is certified in conformance to the American Petroleum Institute Recommended Practice 1173, which is the foundation to our journey towards operational excellence.

Data Center Contracts and Strategy: NIPSCO recently entered into a data center contract with a new customer and entered into amendments to its ADS Contract. Set forth below is a discussion of recent developments relating to our data center contracts and strategy. This discussion is supplemental to, and should be read in conjunction with, our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, in particular Part I, Item 1A, "Risk Factors—Data Center Operations and Strategy Risk" and Part II, Item 7, "Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Summary—ADS Contract and Data Center Strategy."

Alphabet Contract

In March 2026, NIPSCO entered into an agreement with a wholly owned subsidiary of Alphabet, under which NIPSCO will provide electricity to the subsidiary’s data center(the “Alphabet Contract”). Under the Alphabet Contract, which is pending IURC approval, NIPSCO will provide service to Alphabet’s subsidiary pursuant to a capacity commitment beginning in summer 2026 and increasing to 300 MW commencing in 2030. The initial term of the Alphabet Contract is 15 years. Prior to receipt of applicable regulatory approvals from the IURC and FERC, NIPSCO will bill the customer for electric service under its base tariff. Following receipt of regulatory approvals, the customer will pay monthly capacity charges that are based on negotiated rates and actual consumption (subject to certain minimums), together with certain pass-through charges and an existing system charge which will be used to pass savings back to existing customers. The amounts we are entitled to receive from the customer are subject to adjustments including but not limited to resulting from tariff events or MISO accreditation changes. The customer's parent will provide credit support for the customer's payment obligations. Either party may terminate the Alphabet Contract upon certain defaults or failure to obtain necessary related approvals from the IURC and FERC. The Alphabet Contract contains other termination provisions which may be exercised following certain notice periods. If the customer terminates the Alphabet Contract, it is required to make certain termination payments that we believe will be sufficient to reimburse us for our investment costs and NIPSCO has certain obligations to mitigate.

The customer's electricity supply under the Alphabet Contract will be provided through a portfolio of electric generation assets and related assets owned or contracted for by NIPSCO and/or its affiliates (primarily including GenCo) and designed to serve the needs of the customer under the Alphabet Contract and other data center customers (the "Pool Resource Assets"). See “Data Center Strategy & Pool Resource Assets” below for additional information on the Pool Resource Assets. NIPSCO has entered into a PPA with GenCo in connection with the Alphabet Contract, which is pending IURC approval.

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NiSource Inc.

Amendments to ADS Contract

In March 2026, NIPSCO entered into an amendment to its ADS Contract to accelerate the delivery of capacity to ADS, resulting in increased committed capacity in the years 2027 through 2031. The amendment does not increase NIPSCO’s 2,400 MW maximum capacity commitment to ADS under the original ADS Contract but increases the amounts of power to be delivered before the maximum commitment is reached. The amendment is pending IURC approval. Pursuant to the amendment, ADS will regularly pay NIPSCO a fixed capacity charge (not subject to adjustment) from 2027 through 2031, regardless of any termination of the ADS Contract or reduction of capacity. The payment structure under this amendment is distinct from and does not alter the payment structure or the payments NIPSCO will receive under the original ADS Contract. Demand under this amendment is expected to be served through Pool Resource Assets (rather than Contract Assets under the ADS Contract).

In addition, in March and May of 2026, NIPSCO entered into amendments to the ADS Contract, subject to IURC and FERC approval, to increase the committed capacity that NIPSCO will provide beginning in 2029 and increasing to a total capacity commitment of 2,800 MW by the end of 2032 and through the end of the initial term of the ADS Contract. ADS will pay NIPSCO both a fixed capacity charge and an existing system charge designed to pass savings back to existing customers, for the increased capacity. Demand under these amendments is expected to be served through Pool Resource Assets (rather than Contract Assets under the ADS Contract).

Construction Update

GenCo continues to advance development of its new combined‑cycle natural gas‑fired generation facility to support the ADS Contract. During the period, the EPC contractor progressed engineering, procurement, and planning activities in support of construction mobilization currently anticipated in mid‑2026. The equipment supply contract for the CCGT units is progressing in accordance with planned delivery schedules.

GenCo is also advancing the development of a combined 400 MW and 100MW BESS installation. The battery equipment supply contract was awarded in February 2026, and the EPC contractor continues engineering, procurement, and planning activities to support the anticipated start of on-site construction in mid‑2026.

Data Center Strategy & Pool Resource Assets

We continue to experience strong demand from potential data center customers in our northern Indiana service territory and are engaged in negotiations with potential additional counterparties. Agreements we enter into with additional counterparties will be served by means of customized, dedicated generation assets, Pool Resource Assets, or a combination.

With respect to customers to be served by Pool Resource Assets, NIPSCO will retain discretion to select and dispatch Pool Resource Assets to meet committed customer demand in a way that maintains reliability and efficiency without direct involvement or approval from specific customers. We believe this model will enable us to allocate generation resources more efficiently and provide us with greater flexibility to serve a broader range of potential customers.

We evaluate potential transactions with Pool Resource Asset customers in the context of existing demand and resources within the pool in order to promote a sustainable alignment between committed customer demand within the pool and capacity available from Pool Resource Assets. We will add capacity resources to the Pool Resource Assets to maintain resource adequacy requirements and promote efficient resource utilization based on contracts with customers (subject to IURC approval). We anticipate that the total accredited capacity from the pool will be large enough to support the total load requirements of our data center customers taking into consideration MISO requirements. Pool Resource Assets may include generation assets that we develop or contract for (for example, via a BTA), as well as capacity agreements, ESAs, market capacity purchases or other similar agreements. In order to provide initial Pool Resource Assets to serve contracted demand, GenCo plans to construct new battery storage with 100MW nameplate capacity, which is expected to be completed in 2028, and has entered into a number of ESA contracts (including with respect to the Tipton BESS Project, which we intend to convert into a BTA) and other capacity purchase agreements. For more information on these agreements, see Note 13, "Other Commitments and Contingencies - D. Other Matters" – Pool Resource Asset Agreements.” We expect that the capacity provided by these initial Pool Resource Assets will suffice to meet substantially all contracted demand from the second half of 2028 through the expiration of the initial terms of our existing data center contracts.

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NiSource Inc.

Our ability to recover our investments and earn a return under our contracts with customers served by Pool Resource Assets will be driven by, among other factors, the terms of our contracts with these customers (including the charges we receive from customers and any potential adjustments to such charges), our ability to construct or procure sufficient Pool Resource Assets in a timely and cost-effective manner, and the performance by us and our customers under the contracts, rather than a traditional rate-making process.

Through certain of our subsidiaries, we have entered into certain construction and equipment supply contracts in relation to additional

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

EXECUTIVE SUMMARY

This Management's Discussion and Analysis of Financial Condition and Results of Operations ("Management's Discussion") includes management’s analysis of past financial results and certain potential factors that may affect future results, potential future risks and approaches that may be used to manage those risks. See "Note regarding forward-looking statements" and Item 1A, "Risk Factors" at the beginning of this report for a list of factors that may cause results to differ materially. Refer to the "Business" section under Part I, Item 1 of this Annual Report on Form 10-K and Note 21, "Business Segment Information," in the Notes to Consolidated Financial Statements for further discussion of our regulated utility business segments.

This Management's Discussion is designed to provide an understanding of our operations and financial performance and should be read in conjunction with our Consolidated Financial Statements and related Notes to Consolidated Financial Statements in this Annual Report on Form 10-K.

We are an energy holding company under the Public Utility Holding Company Act of 2005 whose primary subsidiaries are fully regulated natural gas and electric utility companies serving customers in six states. We generate substantially all of our operating income through these rate-regulated businesses, which are summarized for financial reporting purposes into two primary reportable segments: Columbia Operations and NIPSCO Operations.

Our vision is to be a premier, innovative and trusted energy partner. We exist to deliver safe, reliable energy that drives value to our customers. In order to achieve this goal, we seek to develop strategies that benefit all stakeholders as we (i) support long-term infrastructure investment and safety programs to better serve our customers, (ii) align our tariff structures and regulatory programs with our cost structure, and (iii) create value and enable growth in an evolving energy ecosystem. These strategies focus on improving safety and reliability, enhancing customer experience, pursuing regulatory and legislative initiatives to increase accessibility for customers currently not on our gas and electric service, ensuring customer value and reducing emissions while generating sustainable returns. The safety of our customers, communities and employees remains our focus. Serving as a guiding practice for our SMS, NiSource is certified in conformance to the American Petroleum Institute Recommended Practice 1173, which is the foundation to our journey towards operational excellence.

2025 Overview:

In 2025, we continued to make significant progress on the remaining portfolio of projects that will enable our electric generation transition, including placing two solar projects and one solar and battery project into service. We advanced our Data Center strategy significantly by creating our GenCo affiliate, whose goal is to build capacity to serve large load customers. We also executed the ADS Contract and related EPC contracts discussed below. During the year, we received orders for four rate cases: Columbia of Maryland, Columbia of Pennsylvania, Columbia of Virginia, and NIPSCO Electric. Between our Columbia and NIPSCO Operating Segments, we added 24,000 customers. We also invested $1.6 billion in infrastructure modernization to enhance safe, reliable service, including replacement of 256 miles of distribution main and service lines, 45 miles of underground cable and 1,656 electric poles. We concluded the second and third phases of a WAM ERP program, covering all gas distribution operations across our operating territories and our generation assets, to optimize the scheduling, dispatch, and execution of our field operations.

ADS Contract and Data Center Strategy:

ADS Contract

In September 2025, NIPSCO entered into an agreement with ADS, a wholly-owned subsidiary of Amazon.com, Inc., under which NIPSCO will provide electricity to ADS' data centers. Under the ADS Contract, which is pending IURC approval, NIPSCO will provide electric service to ADS pursuant to a capacity commitment beginning in 2027 and increasing annually to

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2,400 MW by the end of 2032 and will construct up to 3,000 MW of dispatchable generation to provide such electric service. The ADS Contract’s initial term ends 15 years after the initial energization of ADS’ initial data center. Starting January 2027, ADS will regularly pay NIPSCO a fixed capacity charge and certain pass-through charges. Amazon.com, Inc. a publicly traded, investment-grade parent company has guaranteed ADS’ payment obligations. These charges are structured to provide us with a return of our invested capital over the fifteen-year initial term. In addition, the ADS Contract contains provisions for adjustment of the charges designed to provide us with an unlevered internal rate of return on our invested capital over the initial term within a defined range, which we expect over the life of the ADS contract to result in an overall realized return greater than that of NIPSCO’s current electric operations, driven by execution and financing. Our realized return may be impacted by factors such as construction costs, operating performance, financing costs and other variables. NIPSCO will also propose to the IURC a mechanism to pass savings back to retail customers for use of the existing system which is expected to begin in 2027. Refer to Part I, Item 1A, “Risk Factors” for a discussion of certain of these factors and other risks relating to the ADS Contract.

In order to meet demand under the ADS Contract, NIPSCO has entered into a PPA with GenCo, which is pending IURC approval and contains terms and provisions substantially similar to the ADS Contract, such that economic benefits (except savings that are expected to be passed to retail customers as described above) and obligations of the ADS Contract as they relate to the Generation Assets (as defined below) are expected to be borne by GenCo and NiSource, as GenCo’s ultimate parent company, rather than NIPSCO.

GenCo plans to construct 400 MW of new battery storage and a new power generation facility consisting of two 1,300 MW CCGTs, which are expected to reach commercial operation between 2028 and 2032 (such assets, collectively, the “Generation Assets”). NIPSCO currently has a proceeding before the IURC to approve the generation facilities required to be built for ADS. GenCo has entered into engineering, procurement and construction contracts (the “EPC Contracts”), and certain equipment supply contracts, including a contract to acquire turbines, with respect to the construction of the Generation Assets. The aggregate cost of the Generation Assets, together with the cost to develop related transmission infrastructure (collectively, the “Contract Assets”), is currently estimated to be approximately $7 billion. The EPC Contracts provide certain protections against cost overruns, and any excess costs with respect to the EPC Contracts beyond those protections, or arising apart from the EPC Contracts are, unless otherwise agreed by the parties, shared by ADS and NIPSCO (for transmission) and GenCo (for generation). If the Contract Assets are delivered into service late or do not achieve certain performance-related milestones, ADS is entitled to liquidated damages, subject to a cap and offset against the regular charges paid by ADS.

Either party may terminate the ADS Contract upon certain defaults or failure to obtain necessary related approvals from the IURC and FERC. ADS may terminate the ADS Contract for convenience following certain notice periods and also has a one-time option (exercisable no later than March 31, 2029) to halve the committed capacity under the ADS Contract to 1,200 MW commencing January 31, 2032. If ADS terminates for convenience, exercises its reduction option or defaults, NIPSCO or its affiliates will be reimbursed for investment costs, subject to agreed caps based on cost estimates by year as of signing. NIPSCO’s aggregate liability, including liquidated damages, is subject to a cap.

NIPSCO’s and GenCo’s operations under the ADS Contract will be regulated by the IURC in a different way from the regulatory mechanisms applicable to NIPSCO’s historical operations. The terms of the ADS Contract were determined by commercial negotiation with ADS. These terms include the charges we receive from ADS and provisions that may result in adjustments to such charges, including those relating to certain liquidated damages that we may owe ADS in the event of construction delays or capacity shortfalls, the parties’ responsibility to share cost overruns, certain changes in law and force majeure events. The IURC will not determine the commercial terms of the ADS Contract; however, the IURC will maintain oversight under the ADS Contract to ensure NIPSCO provides reliable service to ADS at just and reasonable rates. In order to recover our investment costs and earn our return under the ADS Contract, our subsidiaries must efficiently perform their own obligations and must look to ADS (or its parent guarantor) to perform its obligations, rather than the IURC making use of its traditional rate-making process. In addition, under the ADS Contract, NIPSCO has direct contractual obligations to ADS to, among other things, construct the Contract Assets and deliver committed electric capacity in fixed amounts by certain dates.

The terms of any future data center contracts we enter into may differ from the terms of the ADS Contract. For example, customer demand may not be served through designated assets and may contemplate that capacity will be procured via PPAs with third parties. However, the terms of any future data center contracts (including the charges we receive from customers and any potential adjustments to such charges) will inform our ability to recover our investments and earn a return. Similar to the ADS Contract, any additional data center contracts will be subject to IURC approval and oversight authority, but the IURC will not determine the commercial terms.

Data Center Strategy

We continue to experience strong demand from potential data center customers in our northern Indiana service territory and are engaged in negotiations with potential counterparties. Through certain of our subsidiaries, we have entered into certain

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construction and equipment supply contracts in relation to additional generation and transmission assets that may be used to serve potential future data center customers. As we continue to evaluate our potential data center opportunities, we will continue to focus on the community, financial, operational and regulatory factors that must be managed effectively in order to succeed with our data center strategy. We believe data center development can enhance our local tax base, diversify the employment base across the state of Indiana, and provide greater value to existing customers and shareholders. We continually evaluate ways to effectively manage the potential power demand, generation sources, and transmission capabilities to meet potential further load growth from additional data center customers, while at the same time focusing on our environmental goals.

In order to perform under any further data center contracts, we expect that we would need to develop additional generation and transmission assets, which may be significant, and obtain additional financing in connection with such development. For these and other reasons, our ability to successfully execute our data center strategy is subject to a number of risks and uncertainties. Refer to Part I, Item 1A, “Risk Factors” for a discussion of certain risks relating to our data center strategy.

Energy Transition:

We continue to advance our energy transition strategy, primarily through the continuation and enhancement of existing programs, such as implementing our plan to retire and replace remaining coal-fired electric generation by 2028 with a balanced mix of low- or zero-emission electric generation, ongoing pipe replacement and modernization programs, and deployment of advanced leak detection and repair. We continue to make progress on our electric generation transition, initiated through our 2018 Integrated Resource Plan ("2018 Plan"), and we are continually adjusting to the dynamic energy landscape. As of December 31, 2025, we have placed in service owned renewable and storage projects with combined nameplate capacities of 1,950 MW and 101 MW respectively. Renewable PPA projects with a combined nameplate capacity of 1,200 MW have also been placed in service. For additional information, see Note 14, "Other Commitments and Contingencies - D. Other Matters". In December 2025, before the planned retirement of the R.M. Schahfer coal facility, the U.S. Secretary of Energy issued an emergency order under section 202(c) of the Federal Power Act requiring R.M. Schahfer to continue operating for 90 days, through March 2026. The order stated that continued operation of R.M. Schahfer was required to meet an energy emergency across MISO’s North and Central regions and authorizes NIPSCO to obtain cost recovery pursuant to 16 U.S.C. § 824a(c). For additional information, see "Results and Discussion of Operations - NIPSCO Operations," in this Management's Discussion, and see Part I, Item 1A. "Risk Factors" in this Annual Report on Form 10-K.

NIPSCO's 2021 Plan calls for a new natural gas peaking facility to replace existing vintage gas peaking facilities at the R.M. Schahfer Generating Station to support system reliability and resiliency, and upgrades to the electric transmission system. Following approval by the IURC in October 2024, the construction of a new 400 MW natural gas peaking generation facility is underway, which is expected to support the planned retirement of the existing vintage gas peaking facilities by the end of 2028. The 2021 Plan affirm's Michigan City 2028 retirement and calls for new natural gas peaking facilities. Final retirement dates for these units will be subject to MISO approval.

NIPSCO's 2024 Integrated Resource Plan ("2024 Plan") was submitted to the IURC on December 9, 2024. The 2024 Plan maintains the retirement decisions and capacity additions identified in the 2018 and 2021 Integrated Resource Plans and calls for additional generation resources through 2029 to support capacity requirements. The 2024 Plan informs future generation investments required to ensure reliability for NIPSCO’s customers and incorporates factors such as anticipated load growth from data centers and other economic development opportunities, EPA emissions rules, and evolving MISO resource accreditation rules. Given that the 90-day 202(c) order could continue to be issued every 90 days to keep Schahfer Units 17 & 18 open for the foreseeable future, and given that MISO's resource accreditations for renewables and storage remain uncertain, it may be necessary to evaluate changes to our previously communicated resource timelines and alternative resource decisions. We plan to move as efficiently as possible while maintaining the integrity of our commercial, planning, regulatory, procurement and operational execution processes.

We continue to enhance safety and reduce methane emissions on our gas systems through modernization programs and utilization of advanced leak detection and repair. In addition, we plan to advance other low- or zero-emission energy resources and technologies, such as hydrogen and renewable natural gas.

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Transformation:

We are modernizing and unlocking efficiencies within our systems and processes on operational excellence, safety, operation and maintenance management. These efforts include investments in proven technologies backed with standardized processes that will change the way we plan, schedule, and execute work in the field and how we engage and provide service to our customers. We delivered the first major milestones of our transformation roadmap through the implementation of phases of our WAM ERP program, foundational AMI capabilities, and completion of certain cyber enhancements to continue to advance the cybersecurity program. Our WAM ERP program has been implemented across our electric and transmission operations, all gas distribution operations and our generation assets. This ERP system standardizes processes around the design and build of our assets as well as optimizes the scheduling, dispatch, and execution of our field operations. We continue to focus on our customer technology platforms. In addition to transforming technology to enhance our employee and customer experiences, we believe these programs will modernize systems and further reduce our enterprise risk related to end-of-life systems.

Economic Environment:

We continue to monitor risks related to order and delivery lead times for construction and other materials, potential unavailability of materials due to global shortages in raw materials, and decreased construction labor productivity in the event of disruptions in the availability of materials. We continue to experience elevated material and supply costs in certain product sourcing categories driven by increased demand and tariffs. To the extent that work plan delays occur or our costs increase, our business operations, results of operations, cash flows, and financial condition could be materially adversely affected. Refer to Part I, Item 1A. Risk Factors, "Financial, Economic and Market Risks" of this Annual Report on Form 10-K for further detail.

We are faced with increased competition for employee and contractor talent in the current labor market which has resulted in increased costs to attract and retain talent. We are ensuring that we use all internal human capital programs (development, leadership enablement programs, succession, performance management) to promote retention of our current employees along with having a competitive and attractive appeal for potential recruits. Our flexible work arrangements, where possible, support a broader talent footprint for sourcing talent needed and for remaining competitive.

We continue to evaluate our financing plan to manage interest expense and exposure to rates. For more information on interest rate risk, see "Market Risk Disclosures" and Part I, Item 1A. Risk Factors, "Financial, Economic and Market Risks" of this Annual Report on Form 10-K.

NIPSCO Minority Interest Transaction:

In December 2023, contemporaneously with the closing of the NIPSCO Minority Interest Transaction, Blackstone, NIPSCO Holdings I, NIPSCO Holdings II, and NiSource entered into an Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II. In January 2024, BIP transferred its equity interest to one of its affiliates and the members of NIPSCO Holdings II entered into a Second Amended and Restated Limited Liability Company Operating Agreement of NIPSCO Holdings II. In October 2025, the members of NIPSCO Holdings II entered into a Third Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II (the "Amended LLC Agreement"), which, among other changes, increased the amount and time period for additional mandatory capital contributions required to be contributed by the members affiliated with Blackstone by $175 million and seven years, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof, and amended certain provisions to facilitate NIPSCO Holdings II and its subsidiaries' provision of electric service to data center customers (and related activities) and their related contracts and arrangements with Generation Holdings II and its subsidiaries. The members of NIPSCO Holdings II that are affiliates of Blackstone must vote their equity holdings under the Amended LLC Agreement as one investor. Refer to Note 4, "Noncontrolling Interests," in the Notes to the Consolidated Financial Statements for more information on this transaction.

GenCo Minority Equity Interest Transaction:

In October 2025, NiSource issued a 19.9% equity interest in NiSource’s wholly-owned subsidiary Generation Holdings II to BIP Orion Holdco L.P. and BIP Orion Holdco II L.P., affiliates of Blackstone (collectively, “Blackstone Investor”), in exchange for $35.2 million in cash contributions to Generation Holdings II through an Amended and Restated Limited Liability Company Agreement of Generation Holdings II (the Generation Holdings II “LLC Agreement”). Generation Holdings II is the sole owner of GenCo.

The Generation Holdings II LLC Agreement establishes, among other things, governance rights, exit rights, requirements for additional capital contributions, mechanics for distributions, and other arrangements for Generation Holdings II. Specifically,

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under the terms of the Generation Holdings II LLC Agreement, Blackstone Investor will provide up to $1.325 billion in additional capital contributions over a seven-year period, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof. Under the Generation Holdings II LLC Agreement, Blackstone Investor is entitled to appoint two directors to the board of directors of Generation Holdings II (the “Holdings II Board”) so long as Blackstone Investor (together with any approved affiliate) holds at least a 17.5% Percentage Interest (as defined in the Generation Holdings II LLC Agreement). Blackstone Investor appointed two directors to the Holdings II Board, such that the Holdings II Board is comprised of seven directors, two appointed by Blackstone Investor and five appointed by NiSource. The Generation Holdings II LLC Agreement also contains certain investor protections, including, among other things, requiring Blackstone Investor approval for Generation Holdings II to take certain major actions outside of the normal course of business. In addition, the Generation Holdings II LLC Agreement contains certain terms surrounding transfer rights and other obligations applicable to both Blackstone Investor and NiSource. Under the Generation Holdings II LLC Agreement, Generation Holdings II has agreed that, so long as Blackstone Investor holds a 14.9% or greater percentage interest in Generation Holdings II, Generation Holdings II, NIPSCO Holdings II (as defined below) and/or their respective subsidiaries will be the exclusive vehicles for all power, storage and generation requirements for data center customers within NIPSCO’s service territory. The Generation Holdings II LLC Agreement also establishes that NiSource will be attributed 80.1% of any profit or loss from Generation Holdings II, through its wholly owned subsidiary GenCo, with the Blackstone Investor being attributed the remaining 19.9% of any profit or loss.

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)

Summary of Consolidated Financial Results

A summary of our consolidated financial results for the years ended December 31, 2025, 2024 and 2023, are presented below:

The majority of the costs of energy in both segments are tracked costs that are passed through directly to the customer, resulting in an equal and offsetting amount reflected in operating revenues.

The increase in net income available to common shareholders during 2025 was primarily due to higher revenues, net of cost of energy, driven by our continued investment in safety and successful regulatory outcomes for these investments, reliability and low- or zero-emission generation year-over-year. The increase in net income available to common shareholders is partially offset by higher operation and maintenance expense, higher depreciation expense attributed to our planned capital expenditures, and increased interest expense.

For additional information on operating income variance drivers see "Results and Discussion of Operations" for Columbia Operations and NIPSCO Operations in this Management's Discussion.

Other Deductions, Net

The change in Other deductions, net in 2025 compared to 2024 is primarily driven by higher long-term debt interest in 2025 and lower AFUDC in 2025 driven by lower CWIP outstanding year-over-year. See Note 7, "Short-Term Borrowings," Note 8, "Long-Term Debt," Note 22, "Other, Net,"and Note 23, "Interest Expense, Net," in the Notes to Consolidated Financial Statements for additional information.

Income Taxes

The increase in income tax expense in 2025 compared to the same period in 2024 is primarily due to higher pre-tax income, partially offset by the tax effect of non-controlling interest. Refer to Note 15, "Income Taxes," in the Notes to Consolidated Financial Statements for additional information on income taxes and the change in the effective tax rate.

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RESULTS AND DISCUSSION OF OPERATIONS

Presentation of Segment Information

Columbia Operations aggregates the results of the fully regulated and wholly owned subsidiaries of NiSource Gas Distribution Group, Inc. Each Columbia distribution company is an operating segment which we aggregate to form the Columbia Operations reportable segment. NIPSCO Operations aggregates the results of NIPSCO Holdings I, and its majority-owned subsidiaries, including NIPSCO, which has both 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" within the Notes to the Condensed Consolidated Financial Statements (unaudited) and primarily are comprised of interest expense on holding company debt, unallocated corporate costs and activities and new business development costs associated with GenCo.

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Columbia Operations

Financial and operational data for the Columbia Operations segment for the years ended December 31, 2025, 2024 and 2023, are presented below:

(1) Heating degree figures represent averages of the five jurisdictions served by Columbia Operations.

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Columbia Operations (continued)

Comparability of operation and maintenance expenses, depreciation and amortization, and other taxes may be impacted by regulatory, depreciation and tax trackers that allow for the recovery in rates of certain costs.

The underlying reasons for changes in our operating revenues and expenses from 2025 to 2024 are presented in the respective tables below.

Weather

In general, we calculate the weather-related revenue variance based on changing customer demand driven by weather variance from normal heating degree days, net of weather and revenue normalization mechanisms. Our composite heating degree days reported do not directly correlate to the weather-related dollar impact on the results of Columbia Operations. Heating degree days experienced during different times of the year or in different operating locations may have more or less impact on volume and dollars depending on when and where they occur. When the detailed results are combined for reporting, there may be weather-related dollar impacts on operations when there is not an apparent or significant change in our aggregated composite heating degree day comparison.

Throughput

The increase in total volumes sold and transported in 2025 compared to 2024 of 46.2 MMDth is primarily attributable to the effects of colder weather.

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Columbia Operations (continued)

Commodity Price Impact

Cost of energy for the Columbia Operations segment is principally comprised of the cost of natural gas procured on behalf of and sold to customers while providing transportation services. All of our Columbia Operations companies have state-approved recovery mechanisms that provide a means for full recovery of prudently incurred gas costs. These are tracked costs that are passed through directly to the customer, and the gas costs included in revenues are matched with the gas cost expense recorded in the period. Any difference in actual costs incurred and amounts billed to customers is recorded on the Consolidated Balance Sheets as under-recovered or over-recovered gas cost to be included in future customer billings. Therefore, increases in these tracked operating expenses are offset by increases in operating revenues and have essentially no impact on net income. Certain Columbia Operations companies continue to offer choice opportunities, where customers can choose to purchase gas from a third-party supplier, through regulatory initiatives in their respective jurisdictions.

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NIPSCO Operations

Financial and operational data for the NIPSCO Operations segment, which services both gas and electric customers, for the years ended December 31, 2025, 2024 and 2023, are presented below:

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NIPSCO Operations

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NIPSCO Operations (continued)

Comparability of operation and maintenance expenses and depreciation and amortization may be impacted by regulatory and depreciation trackers that allow for the recovery in rates of certain costs.

The underlying reasons for changes in our operating revenues and expenses from 2025 to 2024 are presented in the respective tables below.

Weather

The results of operations for the NIPSCO Operations segment include income from both electric and gas service lines. In general, we calculate the weather-related revenue variance based on changing customer demand driven by weather variance from normal cooling degree days and normal heating degree days, net of NIPSCO Gas' weather normalization mechanisms. Our composite cooling and heating degree days reported do not directly correlate to the weather-related dollar impact on the results of NIPSCO Operations. Cooling and heating degree days experienced during different times of the year or in different operating locations may have more or less impact on volume and dollars depending on when they occur. When the detailed results are combined for reporting, there may be weather-related dollar impacts on operations when there is not an apparent or significant change in our aggregated composite cooling and heating degree day comparison.

Sales

The increase in total volumes sold to electric customers for twelve months ended December 31, 2025 compared to the same period in 2024 was primarily attributable to residential customer growth and increased usage by commercial customers, partially offset by a decrease in usage by industrial customers. NIPSCO Electric results remains closely linked to the performance of the steel industry. MWh sales to steel-related industries accounted for approximately 49.3% and 49.4% of the total industrial MWh sales for the years ended December 31, 2025 and 2024, respectively.

The increase in total volumes sold to gas customers for the twelve months ended December 31, 2025 compared to the same period in 2024 was primarily attributable to colder weather, as well as residential and commercial customer count growth.

Commodity Price Impact

Cost of energy for the NIPSCO Operations segment's electric activities is principally comprised of the cost of coal, natural gas purchased for internal generation of electricity, transportation of coal and natural gas, and the cost of power purchased from generators of electricity for its generation and transmission activities. For its gas distribution activities, NIPSCO Operations' cost of energy is principally comprised of the cost of natural gas procured on behalf of and sold to customers while providing transportation and distribution services. NIPSCO Operations has state-approved recovery mechanisms that provides a means for full recovery of prudently incurred costs of energy. The majority of these costs of energy are passed through directly to the customer, and the costs of energy included in operating revenues are matched with the cost of energy expense recorded in the

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NIPSCO Operations (continued)

period. Any difference in actual costs incurred and amounts billed to customers is recorded on the Consolidated Balance Sheets as under-recovered or over-recovered fuel and gas cost to be included in future customer billings. Therefore, increases in these tracked operating expenses are offset by increases in operating revenues and have essentially no impact on net income.

The underlying reasons for changes in our operating expenses for the twelve months ended December 31, 2025 compared to the same period in 2024 are presented below.

Electric Supply and Generation Transition

NIPSCO continues to execute on an electric generation transition consistent with the 2018 Plan and 2021 Plan and maintained in the 2024 Plan. See "Liquidity and Capital Resources" in this Management's Discussion for additional information on our capital investment spend. NIPSCO is responding to federal and state executive orders, or other regulatory actions, with respect to its generation transition plans. In December 2025, before the planned retirement of the R.M. Schahfer coal facility, the U.S. Secretary of Energy issued an emergency order under section 202(c) of the Federal Power Act requiring R.M. Schahfer to continue operating for 90 days, through March 23, 2026. The order stated that continued operation of R.M. Schahfer was required to meet an energy emergency across MISO’s North and Central regions. Consistent with the Federal Power Act and the U.S. Department of Energy regulations, the order authorizes NIPSCO to obtain cost recovery pursuant to 16 U.S.C. § 824a(c). As directed, NIPSCO continued to make R.M. Schahfer available in the MISO market. Following receipt of the emergency order, NIPSCO filed a complaint at FERC seeking a modification of the MISO Tariff to establish a mechanism for recovery and allocation of the cost to comply with this order. NIPSCO made two filings with the IURC related to the emergency order. The first filing is to confirm accounting treatment of current electric rate order, and the second is a filing for recovery of federally mandated expenses related to the emergency order, which will be utilized in the event that any costs of complying with the emergency order fall outside of the MISO Tariff recovery. For additional information, see Note 12, "Regulatory Matters,".

Since 2020, five PPA projects (three wind and two solar) and eight owned projects (two wind, four solar and two solar plus storage) have been placed into service totaling approximately 3,246 MW of nameplate capacity, including Dunn's Bridge II, Fairbanks, Gibson, Appleseed, and Carpenter, which were placed into service in January, May, August, and December 2025, respectively. NIPSCO has executed several PPAs to purchase 100% of the output from renewable generation facilities at a fixed price per MWh. Each facility supplying the energy has an associated nameplate capacity, and payments under the PPAs do not begin until the associated generation facility is placed into service. We expect the Templeton project, a wind BTA project with a nameplate capacity of 200 MW, to be placed in service in 2027. See "Executive Summary - Energy Transition" in this Management's Discussion for additional information. NIPSCO has sold, and may in the future sell, renewable energy credits from its renewable generation to third parties to offset customer costs.

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Liquidity and Capital Resources

We continually evaluate the availability of adequate financing to fund our ongoing business operations, working capital and core safety and infrastructure investment programs. Our financing is sourced through cash flow from operations, the issuance of debt and/or equity, and minority interest investments in NIPSCO Holdings II and Generation Holdings II. Equity issuances are primarily conducted through our ATM program. Additionally, we received proceeds from tax credit transfers associated with the monetization of credits of $22.4 million and $23.5 million for the years ended December 31, 2025 and 2024, respectively. External debt financing is provided primarily through the issuance of long-term debt, accounts receivable securitization programs and our $1.85 billion commercial paper program, which is backstopped by our committed revolving credit facility. In December 2025, we increased our revolving credit facility availability from $1.85 billion to $2.50 billion from third-party lenders. We believe these sources provide adequate capital to fund our operating activities and capital expenditures in 2026 and beyond.

As discussed above under “ADS Contract and Strategy,” the aggregate cost of the Contract Assets is currently estimated to be approximately $7 billion. We expect to finance the construction and development of these assets through a number of sources including but not limited to funds received under the ADS Contract, debt and equity financing raised by NiSource and capital contributions from affiliates of Blackstone to NIPSCO Holdings II and Generation Holdings II in connection with such Blackstone affiliates’ minority interest investments in those entities. For additional information on these minority interest investments, refer to Note 4, "Noncontrolling Interests," and Note 19, "Other Commitments and Contingencies - E. Other Matters," included herein. If we enter into additional data center contracts, we expect that we would need to develop additional generation assets to serve our new data center customers. In order to fund the development of these assets which may be significant, we would be required to obtain significant additional financing, for which we may consider other funding sources, structures, or partnerships such as JVs or off-balance sheet arrangements in the form of BTAs to support maintenance of our investment grade credit ratings.

Sources of financing activities for the current year are as follows:

Details of our 2024 ATM program activity are summarized below:

•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.

•In October 2025, with the commencement of our 2025 ATM program discussed below, we terminated the equity distribution agreements entered into in February 2024 in connection with the 2024 ATM program.

Details of our 2025 ATM program activity are summarized below:

•In October 2025, we entered into eleven separate equity distribution agreements providing for the sale of up to an aggregate of $1.5 billion of our common stock.

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•In October 2025, we executed a direct sale agreement of 1,195,029 shares at a price of $41.84 resulting in net proceeds of $49.6 million received in November 2025.

•In October 2025, we executed a forward sale agreement, which allows 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 2,390,057 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $41.84 per share. We may settle the forward sale agreement in shares, cash or net shares by October 2026. Had we settled all of the shares under the forward sale agreement at December 31, 2025, we would have received approximately $99.7 million, based on a net price of $41.73 per share.

•As of December 31, 2025 the 2025 ATM program inclusive of the forward sale agreement had approximately $1.35 billion of equity capacity available. The 2025 ATM program expires in December 2028.

Details of our 2025 long-term debt activity are summarized below:

•In March 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.

•In June 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 in March 2025. With the incremental issuance, we now have $1.5 billion of 5.850% senior unsecured notes maturing in 2055. In June 2025, we also completed the issuance and sale of $900.0 million of 5.350% senior unsecured notes maturing in 2035 (the "2035 Notes"). These issuances of the 2055 Notes and the 2035 Notes resulted in approximately $1.616 billion of total net proceeds after discount and debt issuance costs.

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

•In November 2025, we completed the issuance and sale of $1.0 billion of 5.750% fixed-to-fixed reset rate junior subordinated notes maturing in 2056, which resulted in approximately $984.3 million of net proceeds after debt issuance costs.

•In December 2025, Columbia of Massachusetts repaid $10.0 million of 6.430% medium term notes at maturity.

See Note 4, "Noncontrolling Interests,", Note 6, "Equity," Note 7, "Short-Term Borrowings," and Note 8, "Long-Term Debt," in the Notes to the Consolidated Financial Statements for more information.

Operating Activities

Net cash from operating activities for the year ended December 31, 2025 was $2,362.3 million, an increase of $580.8 million from 2024. This increase in cash from operating activities was primarily attributable to higher net income, depreciation expense, deferred taxes, supplier refunds received in 2025 and decreases in current year exchange gas receivables in 2025 compared to 2024.

Investing Activities

Net cash used for investing activities for the year ended December 31, 2025 was $4,524.1 million, an increase of $1,311.1 million from 2024. The year over year increase in investing activities was primarily comprised of milestone payments to renewable generation asset developers for certain of our BTA projects, advanced deposits, and additional capital expenditures in 2025 compared to 2024.

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Capital Expenditures. The table below reflects actual capital expenditures and certain other investing activities by segment for 2025.

(1)Certain amounts may subsequently be allocated out of Corporate and Other Maintenance Costs to the Columbia Operations and NIPSCO Operations segments when placed in service. This amount also includes $39.7 million related to data center generation assets.

(2)Amounts differ from those presented on the Statements of Consolidated Cash Flows primarily due to the capitalized portion of the Corporate Incentive Plan payout, inclusion of capital expenditures included in current liabilities and AFUDC Equity.

In addition to these capital expenditures, we invested $70.5 million in cloud computing costs in 2025. We also made $373.8 million in advanced deposits for project costs to secure certain long lead equipment related to data center generation assets.

We expect to make capital investments totaling approximately $21.0 billion during the 2026-2030 period to support our base business (exclusive of investments relating to the ADS Contract), including capital investments to support our generation transition strategy, and to invest approximately $7.0 billion during that period to develop the Contract Assets in connection with the ADS Contract, as set forth in the table below. As discussed above, if we enter into additional data center contracts, we expect to make significant further capital investments in addition to those set forth in the table below, and/or to consider alternative financing structures such as JVs or off-balance sheet arrangements. The forecasted capital investments are subject to continuing review and adjustment. Actual capital investments may vary from these estimates.

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Regulatory Capital Programs. We continue to upgrade and modernize our electric system to enhance safety and reliability by addressing aged infrastructure and deploying advanced grid technologies. We are also upgrading and modernizing our gas infrastructure to enhance safety and reliability by reducing leaks. An ancillary benefit of these programs is the reduction of GHG emissions. In 2025, we continued to move forward on core infrastructure investment programs supported by complementary regulatory and customer initiatives across five states of our operating area.

The following table describes the most recent vintage of our regulatory programs to recover infrastructure replacement and other federally mandated compliance investments:

(1)Programs do not include any costs already included in base rates.

(2)TDSIC – 7 was originally filed in May 2025 and refiled in July 2025, due to the electric rate case order. The refiling adjusted the capital in the tracker from $744.7 million to $315.6 million.

(3)Capital investment is based on a projected amount. The capital investment has not all been incurred to date and represents a forecasted average for the billing period.

Columbia of Ohio filed an application in December 2025. The application seeks to continue Columbia of Ohio's PHMSA IRP Rider for calendar year 2027. The request includes recovery of $404.3 million of capital to reconfirm maximum allowable operating pressure of transmission class pipe to meet federal rule requirements.

NIPSCO filed a Gas TDSIC Plan (2026 - 2030) in December 2025. The petition is seeking recovery of new or replacement projects undertaken for the purpose of safety, reliability, system modernization, or economic development. The request includes $764.7 million of estimated capital, including indirect costs and AFUDC.

Refer to Note 12, "Regulatory Matters," in the Notes to Consolidated Financial Statements for a further discussion of regulatory developments during 2025.

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Financing Activities

Common Stock, Preferred Stock and Equity Unit Sale. Refer to Note 6, "Equity," in the Notes to Consolidated Financial Statements for information on common stock, preferred stock and equity units activity.

Short-term Debt. Refer to Note 7, "Short-Term Borrowings," in the Notes to Consolidated Financial Statements for information on short-term debt.

Long-term Debt. Refer to Note 8, "Long-Term Debt," in the Notes to Consolidated Financial Statements for information on long-term debt.

Non-controlling Interest. Refer to Note 4, "Noncontrolling Interests," in the Notes to Consolidated Financial Statements for more information.

Sources of Liquidity

The following table displays our liquidity position as of December 31, 2025 and 2024:

(1)Represents the lesser of the seasonal limit or maximum borrowings supportable by the underlying receivables.

Debt Covenants. We are subject to a financial covenant under our revolving credit facility which requires us to maintain a debt to capitalization ratio that does not exceed 70%. As of December 31, 2025, the ratio was 51.0%.

Credit Ratings. The credit rating agencies periodically review our ratings, taking into account factors such as our capital structure and earnings profile. The following table includes our and NIPSCO's credit ratings and ratings outlook as of December 31, 2025.

A credit rating is not a recommendation to buy, sell or hold securities, and may be subject to revision or withdrawal at any time by the assigning rating organization.

Certain of our subsidiaries have agreements that contain “ratings triggers” that require increased collateral if our credit ratings or the credit ratings of certain of our subsidiaries are below investment grade. These agreements are primarily for insurance purposes and for the physical purchase or sale of power. As of December 31, 2025, a collateral requirement of approximately $150.2 million would be required in the event of a downgrade below investment grade. In addition to agreements with ratings triggers, there are other agreements that contain “adequate assurance” or “material adverse change” provisions that could necessitate additional credit support such as letters of credit and cash collateral to transact business.

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Equity. Our authorized capital stock consists of 770,000,000 shares, $0.01 par value, of which 750,000,000 are common stock and 20,000,000 are preferred stock. As of December 31, 2025, 478,432,058 shares of common stock were outstanding and no shares of preferred stock were outstanding. For more information regarding our common and preferred stock, see Note 6, "Equity," in the Notes to Consolidated Financial Statements.

Contractual Obligations, Cash Requirements and Off-Balance Sheet Arrangements

We have certain contractual obligations requiring payments at specified periods. Our material cash requirements are detailed below. We intend to use funds from the liquidity sources referenced above to meet these cash requirements.

At December 31, 2025, we had $15,477.5 million in long-term debt, of which $19.7 million is current, and $736.0 million in short-term borrowings outstanding.

During 2026 and 2027, we expect to make cash payments of $809.5 million and $879.3 million, respectively, related to pipeline service obligations including demand for gas transportation, gas storage and gas purchases, and $87.6 million and $10.4 million, respectively, for long lead time items related to plant equipment purchases.

Our expected payments include employer contributions to pension and other postretirement benefits plans expected to be made in 2026. Plan contributions beyond 2026 are dependent upon a number of factors, including actual returns on plan assets, which cannot be reliably estimated at this time. In 2026, we expect to make contributions of approximately $2.7 million to our pension plans and approximately $18.3 million to our postretirement medical and life plans. Refer to Note 16, "Pension and Other Postemployment Benefits," in the Notes to Consolidated Financial Statements for more information.

We cannot reasonably estimate the settlement amounts or timing of cash flows related to asset retirement obligations on the Consolidated Balance Sheets.

We have uncertain income tax positions for which we are unable to predict when the matters will be resolved. Refer to Note 15, "Income Taxes," in the Notes to Consolidated Financial Statements for more information.

NIPSCO has executed several PPAs to purchase 100% of the output from renewable generation facilities at a fixed price per MWh. NIPSCO has also executed several BTAs with developers to construct renewable generation facilities. See Note 19, "Other Commitments and Contingencies - A. Contractual Obligations," and Note 19, "Other Commitments and Contingencies - E. Other Matters," in the Notes to Consolidated Financial Statements for additional information.

In addition, we, along with certain of our subsidiaries, enter into various agreements providing financial or performance assurance to third parties on behalf of certain subsidiaries. Such agreements include guarantees and stand-by letters of credit.

Refer to Note 19, "Other Commitments and Contingencies," in the Notes to Consolidated Financial Statements for additional information regarding our contractual obligations over the next 5 years and thereafter and our off-balance sheet arrangements.

Market Risk Disclosures

Risk is an inherent part of our businesses. The extent to which we properly and effectively identify, assess, monitor and manage each of the various types of risk involved in our businesses is critical to our profitability. We seek to identify, assess, monitor and manage, in accordance with defined policies and procedures, the following principal market risks that are involved in our businesses: commodity price risk, interest rate risk and credit risk. We manage risk through a multi-faceted process with oversight by the Risk Management Committee that requires constant communication, judgment and knowledge of specialized products and markets. Our senior management takes an active role in the risk management process and has developed policies and procedures that require specific administrative and business functions to assist in the identification, assessment and control of various risks. These may include, but are not limited to market, operational, financial, compliance and strategic risk types. In recognition of the increasingly varied and complex nature of the energy business, our risk management process, policies and procedures continue to evolve and are subject to ongoing review and modification.

Commodity Price Risk

Our gas and electric subsidiaries have commodity price risk primarily related to the purchases of natural gas and power. To manage this market risk, our subsidiaries use derivatives, including commodity futures contracts, swaps, forwards and options. We do not participate in speculative energy trading activity.

Commodity price risk resulting from derivative activities at our rate-regulated subsidiaries is limited and does not bear significant exposure to earnings risk, since our current regulatory mechanisms allow recovery of prudently incurred purchased

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power, fuel and gas costs through the rate-making process, including gains or losses on these derivative instruments. These changes are included in the GCA and FAC regulatory rate-recovery mechanisms. If these mechanisms were to be adjusted or eliminated, these subsidiaries may begin providing services without the benefit of the traditional rate-making process and may be more exposed to commodity price risk. For additional information, see "Results and Discussion of Operations" in this Management's Discussion.

Our subsidiaries are required to make cash margin deposits with their brokers to cover actual and potential losses in the value of outstanding exchange traded derivative contracts. The amount of these deposits, some of which are reflected in our restricted cash balance, may fluctuate significantly during periods of high volatility in the energy commodity markets.

Refer to Note 13, "Risk Management Activities," in the Notes to Consolidated Financial Statements for further information on our commodity price risk assets and liabilities as of December 31, 2025 and 2024.

Interest Rate Risk

We are exposed to interest rate risk as a result of changes in interest rates on borrowings under our revolving credit agreement, commercial paper program, and accounts receivable programs, which have interest rates that are indexed to short-term market interest rates. Based upon average borrowings and debt obligations subject to fluctuations in short-term market interest rates, an increase (or decrease) in short-term interest rates of 100 basis points (1%) would have increased (or decreased) interest expense by $8.2 million and $7.9 million for 2025 and 2024, respectively. We are also exposed to interest rate risk as a result of changes in benchmark rates that can influence the interest rates of future long-term debt issuances. From time to time, we may enter into forward interest rate instruments to lock in long term interest costs and/or rates.

Credit Risk

Due to the nature of the industry, credit risk is embedded in many of our business activities. Our extension of credit is governed by a Corporate Credit Risk Management Policy which establishes guidelines for documenting management approval levels for credit limits, evaluating creditworthiness, and credit risk mitigation efforts. Exposures to credit risks are monitored by the risk management function, which is independent of commercial operations. Credit risk arises due to the possibility that a customer, supplier or counterparty will not be able or willing to fulfill its obligations on a transaction on or before the settlement date. For derivative-related contracts, credit risk arises when counterparties are obligated to deliver or purchase defined commodity units of gas or power to us at a future date per execution of contractual terms and conditions. Exposure to credit risk is measured in terms of both current obligations and the market value of forward positions net of any posted collateral such as cash and letters of credit.

The financial status of our banking partners is periodically assessed through traditional credit ratings provided by major credit rating agencies.

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Other Information

Critical Accounting Estimates

We apply certain accounting policies in accordance with GAAP, which require that we make estimates and judgments that have had, and may continue to have, significant impacts on our operations and Consolidated Financial Statements. We evaluate our estimates on an ongoing basis. We base our estimates on historical experience and on various other assumptions that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates. We believe the following represent the more significant items requiring the use of judgment in preparing our Consolidated Financial Statements:

Basis of Accounting for Rate-Regulated Subsidiaries. ASC Topic 980, Regulated Operations, provides that rate-regulated subsidiaries account for and report assets and liabilities consistent with the economic effect of the way in which regulators establish rates, if the rates established are designed to recover the costs of providing the regulated service and if the competitive environment makes it probable that such rates can be billed and collected. Accordingly, certain expenses and credits subject to utility regulation or rate determination normally reflected in income may be deferred on the Consolidated Balance Sheets and recognized in income as the related amounts are included in service rates and recovered from or refunded to customers. For additional information, refer to Note 12, "Regulatory Matters," in the Notes to Consolidated Financial Statements.

In the event that regulation significantly changes the opportunity for us to recover our costs in the future, all or a portion of our regulated operations may no longer meet the criteria for the application of ASC Topic 980, Regulated Operations. In such event, a write-down of all or a portion of our existing regulatory assets and liabilities could result. If transition cost recovery is approved by the appropriate regulatory bodies that would meet the requirements under GAAP for continued accounting as regulatory assets and liabilities during such recovery period, the regulatory assets and liabilities would be reported at the recoverable amounts. If we were unable to continue to apply the provisions of ASC Topic 980, Regulated Operations, we would be required to apply the provisions of ASC Topic 980-20, Discontinuation of Rate-Regulated Accounting. In management’s opinion, our regulated subsidiaries will be subject to ASC Topic 980, Regulated Operations for the foreseeable future.

Certain of the regulatory assets reflected on our Consolidated Balance Sheets require specific regulatory action in order to be included in future service rates. Although recovery of these amounts is not guaranteed, we believe that these costs meet the requirements for deferral as regulatory assets. If we determine that the amounts included as regulatory assets are no longer probable of recovery, a charge to income would immediately be required to the extent of the unrecoverable amounts.

One of the more significant items recorded through the application of this accounting guidance is the regulatory overlay for JV accounting. The application of HLBV to consolidated VIEs generally results in the recognition of profit from the related JVs over a time frame that is different from when the regulatory return is earned. In accordance with the principles of ASC 980, we have recognized a regulatory deferral of certain amounts representing the timing difference between the profit earned from the JVs and the amount included in regulated rates to recover our approved investments in consolidated JVs. For additional information, refer to Note 1, "Nature of Operations and Summary of Significant Accounting Policies - S. Noncontrolling Interest," in the Notes to Consolidated Financial Statements.

Pension and Postretirement Benefits. We have defined benefit plans for both pension and other postretirement benefits. The calculation of the net obligations and annual expense related to the plans requires a significant degree of judgment regarding the discount rates to be used in bringing the liabilities to present value, expected long-term rates of return on plan assets, health care trend rates, and mortality rates, among other assumptions. Due to the size of the plans and the long-term nature of the associated liabilities, changes in the assumptions used in the actuarial estimates could have material impacts on the measurement of the net obligations and annual expense recognition. Differences between actuarial assumptions and actual plan results are deferred into AOCI or a regulatory balance sheet account, depending on the jurisdiction of our entity. These deferred gains or losses are then amortized into the income statement when the accumulated differences exceed 10% of the greater of the projected benefit obligation or the fair value of plan assets (known in GAAP as the “corridor” method) or when settlement accounting is triggered.

The discount rates, expected long-term rates of return on plan assets, health care cost trend rates and mortality rates are critical assumptions. Methods used to develop these assumptions are described below. While a third party actuarial firm assists with the development of many of these assumptions, we are ultimately responsible for selecting the final assumptions.

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The discount rate is utilized principally in calculating the actuarial present value of pension and other postretirement benefit obligations and net periodic pension and other postretirement benefit plan costs. Our discount rates for both pension and other postretirement benefits are determined using spot rates along an AA-rated above median yield curve with cash flows matching the expected duration of benefit payments to be made to plan participants.

The expected long-term rate of return on plan assets is a component utilized in calculating annual pension and other postretirement benefit plan costs. We estimate the expected return on plan assets by evaluating expected bond returns, equity risk premiums, target asset allocations, the effects of active plan management, the impact of periodic plan asset rebalancing and historical performance. We also consider the guidance from our investment advisors in making a final determination of our expected rate of return on assets. For measurement of 2025 net periodic benefit cost, we selected a weighted-average assumption of the expected pre-tax long-term rate of return of 7.30% and 7.09% for our pension and other postretirement benefit plan assets, respectively. For measurement of 2026 net periodic benefit cost, we selected a weighted-average assumption of the expected pre-tax long-term rate of return of 7.13 % and 6.61% respectively, for our pension and other postretirement benefit plan assets.

We estimate the assumed health care cost trend rate, which is used in determining our other postretirement benefit net expense, based upon our actual health care cost experience, the effects of recently enacted legislation, third-party actuarial surveys and general economic conditions.

We utilize a full yield curve approach to estimate the service and interest components of net periodic benefit cost for pension and other postretirement benefits by applying the specific spot rates along the yield curve used in the determination of the benefit obligation to the relevant projected cash flows. For further discussion of our pension and other postretirement benefits, see Note 16, "Pension and Other Postemployment Benefits," in the Notes to Consolidated Financial Statements.

Typically, we use the Society of Actuaries’ most recently published mortality data in developing a best estimate of mortality as part of the calculation of the pension and other postretirement benefit obligations. We adopted Aon's U.S. Endemic Mortality Improvement scale MP-2021, accounting for both the near-term and long-term COVID-19 impacts.

The following tables illustrate the effects of changes in these actuarial assumptions while holding all other assumptions constant:

(1)Before labor capitalization and regulatory deferrals.

Goodwill and Other Intangible Assets. We have six goodwill reporting units, comprised of the six state operating companies within both the Columbia Operations and NIPSCO Operations reportable segments. Our goodwill assets at December 31, 2025 were $1,485.9 million, most of which resulted from the acquisition of Columbia on November 1, 2000.

As required by GAAP, we test for impairment of goodwill on an annual basis and on an interim basis when events or circumstances indicate that a potential impairment may exist. Our annual goodwill test takes place in the second quarter of each year and was performed on May 1, 2025. A qualitative ("step 0") test was completed on May 1, 2025 for all reporting units. In the Step 0 analysis, we assessed various assumptions, events and circumstances that would have affected the estimated fair value of the applicable reporting units as compared to the baseline "step 1" fair value measurement performed May 1, 2024.

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)

The results of this assessment indicated that it was more likely than not that the estimated fair value of the reporting units substantially exceeded the related carrying values of our reporting units; therefore, no "step 1" analysis was required and no impairment charges were indicated. Since the annual evaluation, there have been no indications that the fair values of the goodwill reporting units have decreased below the carrying values.

As noted above, application of the qualitative goodwill impairment test requires evaluating various events and circumstances to determine whether it is not more likely than not that the fair value of a reporting unit is less than its carrying amount. Although we believe all relevant factors were considered in the qualitative impairment analysis to reach the conclusion that goodwill is not impaired, significant changes in any one of the assumptions could potentially result in the recording of an impairment that could have significant impacts on the Consolidated Financial Statements.

See Note 10, "Goodwill," in the Notes to Consolidated Financial Statements for information regarding our 2025 analyses and assumptions.

Unbilled Revenue. We record utility operating revenues when energy is delivered to our customers. However, the determination of energy sales to individual customers is based upon the reading of their meters, which occurs on a systematic basis throughout the month. At the end of each month, amounts of energy delivered to customers since the date of their last meter reading are estimated and corresponding unbilled revenues are calculated. This unbilled revenue is estimated each month based upon historical usage, customer rates and weather. As of December 31, 2025, we recorded $465.2 million of customer accounts receivable for unbilled revenue. Significant fluctuations in energy demand for the unbilled period or changes in the composition of customer classes could impact the accuracy of the unbilled revenue estimate. Refer to Note 3, "Revenue Recognition," in the Notes to Consolidated Financial Statements for additional information regarding our significant judgments and estimates related to unbilled revenue recognition.

Income Taxes. The consolidated income tax provision and deferred income tax assets and liabilities, as well as any unrecognized tax benefits and valuation allowances, require use of estimates and significant management judgment. Although we believe that current estimates for deferred tax assets and liabilities are reasonable, actual results could differ from these estimates for a variety of reasons, including reasonable projections of taxable income, the ability and intent to implement tax planning strategies if necessary, and interpretations of applicable tax laws and regulations across multiple taxing jurisdictions. Ultimate resolution or clarification of income tax matters may result in favorable or unfavorable impacts to net income and cash flows, and adjustments to tax-related assets and liabilities could be material.

We account for uncertain income tax positions using a benefit recognition model with a two-step approach including a more-likely-than-not recognition threshold and a measurement approach based on the largest amount of tax benefit that is greater than 50% likely of being realized upon settlement. We evaluate each position based solely on the technical merits and facts and circumstances of the position, assuming the position will be examined by a taxing authority having full knowledge of all relevant information. Significant judgment is required to determine whether the recognition threshold has been met and, if so, the appropriate amount of tax benefits to be recorded in the consolidated financial statements. At December 31, 2025 and 2024, we had $21.7 million of unrecognized tax benefits. Changes in these unrecognized tax benefits may result from remeasurement of amounts expected to be realized, settlements with tax authorities and expiration of statutes of limitations.

On a quarterly basis, we evaluate our deferred tax assets by considering current and historical financial results, expectations for future taxable income and the availability of tax planning strategies that can be implemented, if necessary, to realize deferred tax assets. Failure to achieve forecasted taxable income or successfully implement tax planning strategies may affect the realization of deferred tax assets. We establish a valuation allowance when we conclude it is more likely than not that all, or a portion, of a deferred tax asset will not be realized in future periods. Significant judgment is required to determine the amount of tax benefits expected to be realized. At December 31, 2025 and 2024, we had established $14.8 million and $6.4 million, respectively, of valuation allowances (net of federal benefit) related to federal Section 163(j) interest limitation carryforward and certain state net operating loss carryforwards. Refer to Note 15, "Income Taxes," in the Notes to Consolidated Financial Statements for additional information.

Recently Issued Accounting Pronouncements

Refer to Note 2, "Recent Accounting Pronouncements," in the Notes to Consolidated Financial Statements.