NISOURCE INC.

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

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 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.

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 throughan 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, 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.