NISOURCE INC.

Cost Recovery and Trackers

Comparability of our line item operating results is impacted by regulatory trackers that allow for the recovery in rates of certain costs such as those described below. Increases in the costs that are subject to approved regulatory tracker mechanisms generally lead to increased regulatory assets, which ultimately result in a corresponding increases in operating revenues and expenses and, therefore, have essentially no impact on total operating income results. Certain approved regulatory tracker mechanisms allow for abbreviated regulatory proceedings in order for the operating companies to quickly implement revised rates and recover associated costs.

A portion of the Columbia Operations' and NIPSCO Operations' revenue is related to the recovery of gas costs, the review and recovery of which occurs through standard regulatory proceedings. All states in our operating area require periodic review of actual gas procurement activity to determine prudence and to confirm the recovery of prudently incurred energy commodity costs supplied to customers.

We recognize that energy efficiency reduces emissions, conserves natural resources and saves our customers money. Our gas distribution companies offer programs such as energy efficiency upgrades, home checkups and weatherization services. The increased efficiency of natural gas appliances and improvements in home building codes and standards contributes to a long-term trend of declining average use per customer. While we are looking to expand offerings so the energy efficiency programs can benefit as many customers as possible, our gas distribution operations utilities have pursued changes in rate design to more effectively match recoveries with costs incurred. Columbia of Ohio has adopted a straight fixed variable rate design for residential and small commercial customers that closely links the recovery of fixed costs with fixed charges. Columbia of Maryland and Columbia of Virginia have regulatory approval for weather and revenue normalization adjustments for certain customer classes, which adjust monthly revenues that exceed or fall short of approved levels. Columbia of Pennsylvania continues to operate its pilot residential weather normalization adjustment and also has a fixed customer charge. This weather normalization adjustment only adjusts revenues when actual weather compared to normal varies by more than 3%. Columbia of Kentucky charges certain customer classes a mix of fixed and weather normalized volumetric rates during the peak heating season. NIPSCO Gas and Electric include a fixed customer charge for residential and small commercial and industrial customer classes. NIPSCO Gas has also received approval and implemented a weather normalization adjustment for certain of its customer classes.

A portion of the NIPSCO Operations' revenue is related to the recovery of fuel costs to generate power and the fuel costs related to purchased power. These costs are recovered through a FAC, which is updated quarterly to reflect actual costs incurred to supply electricity to customers.

While increased efficiency of electric appliances and improvements in home building codes and standards have similarly impacted the average use per electric customer in recent years, NIPSCO expects future growth in per customer usage as a result of increasing electric applications, such as electric vehicles. These ongoing changes in use of electricity will likely lead to development of innovative rate designs, and NIPSCO will continue efforts to design rates that increase the certainty of recovery of fixed costs.

Rate Case Actions

The following table describes current rate case actions as applicable in each of our jurisdictions net of tracker impacts:

(1)No approved ROE is identified for this matter since the approved revenue increase is the result of a black box settlement under which parties agree upon the amount of increase.

(2)The approved rate case resulted in a black box settlement, representing a settlement to a specific revenue increase but not a specified ROE. The settlement provides use of a 9.70% ROE for future SAVE filings.

(3)New rates were implemented in 2 steps, with implementation of Step 1 rates effective in August 2024 and Step 2 rates effective in February 2025.

(4)New rates were implemented in 2 steps, with implementation of Step 1 rates effective in August 2023 and Step 2 rates effective in March 2024.

(5)On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC reflecting an annual revenue increase of $257.0 million. New rates proposed to be implemented in 2 steps, with implementation of Step 1 rates effective no later than September 2025 and Step 2 rates to be effective no later than March 2026.

(6)Rates are effective on an as filed basis and subject to refund. Columbia of Virginia and certain intervening parties, filed a Joint Stipulation and Proposed Recommendation for settlement on December 5, 2024, for an annual revenue increase of $28.2 million, net of SAVE. A hearing examiner’s report was received on February 27, 2025 recommending the adoption of Joint Stipulation and Proposed Recommendation without modification.

PHMSA Legislation and Regulations

To fulfill our vision of being a trusted energy provider, we follow safety practices required by regulations and we implement our Safety Management System ("SMS"). SMS serves as the framework to identify and reduce risks and ensure consistent safety processes, procedures and operations across the organization.

As directed by law in the Protecting Our Infrastructure of Pipelines and Enhancing Safety (PIPES) Act of 2020, PHMSA has revised, and continues to revise, the pipeline safety regulations focused on public safety and environmental hazard mitigation. Specific areas of focus for upcoming rulemaking include leak detection and repair criteria (the "LDAR" rule) and regulations that require operators to upgrade their existing low-pressure regulating stations with enhanced safeguards and update distribution integrity management plans, emergency response plans, and operation and maintenance plans (the Safety of Gas Distribution Pipelines, or "SGDP" rule).

In May 2023, PHMSA proposed regulatory revisions under the PIPES Act of 2020 to minimize methane emissions and improve public safety. Under these proposed revisions, our subsidiaries would be required to detect and repair an increased number of gas leaks, reduce the time to repair leaks, increase leak survey, and expand our existing advanced leak detection program. In January 2025, PHMSA withdrew the final LDAR rule and it has not gone into effect.

In September 2023, PHMSA proposed additional regulatory revisions under the PIPES Act of 2020 to enhance distribution system safety through equipment and procedural expectations in the form of the SGDP rule. Operators will be required to incorporate additional protections for low pressure distribution systems that prevent over-pressurization, amend construction procedures designed to minimize the risk of incidents caused by system over-pressurization, and update distribution integrity management programs to cover and prepare for over-pressurization incidents. PHMSA did not progress the SGDP rulemaking in 2024.

We continue to evaluate and monitor PHMSA legislation and regulations but cannot predict the impact of changing pipeline safety regulations on our business at this time.

Environmental and Climate Change Issues

On March 12, 2025, the EPA announced it will undertake 31 deregulatory actions to advance the administration’s policy priorities as directed by various Executive Orders. These actions will address multiple existing water, waste, air and climate regulations including, but not limited to, GHG rules and the Legacy CCR rule. NiSource will continue to monitor these matters and assess the impacts to our business as regulations are proposed and finalized, or as otherwise required by law.

Physical Climate Risks. Increased frequency of severe and extreme weather events associated with climate change could materially impact our facilities, energy sales, and results of operations. We are unable to predict these events. However, we perform assessments of physical risk, including physical climate risk, to our business. More extreme and volatile temperatures, increased storm intensity and flooding, and more volatile precipitation leading to changes in lake and river levels are among the weather events that are most likely to impact our business. Efforts to mitigate these physical risks continue to be implemented.

Transition Climate Risks and Opportunities. We actively engage with and monitor the impact that proposed legislative and regulatory programs related to GHG emissions, at both the federal and state levels, would have on our business.

Regarding federal policies, we continue to monitor the status of climate change-related legislation and regulation, including the IIJA and IRA and the potential forthcoming budget reconciliation legislation from Congress in 2025. We have identified and pursued potential opportunities associated with the IIJA and the IRA that align with our strategy. These opportunities include tax incentives for renewable generation and storage projects, tax credit transferability and grant funding for grid resiliency, hydrogen hubs and leak detection. The new federal administration has signaled through executive actions a desire to roll-back several climate-related policies including funding for IIJA and IRA programs. We continue to evaluate and monitor how these changes will impact our business.

In May 2024, the EPA published final GHG standards and guidelines for fossil fuel-fired power plants. The rules are not expected to impact NIPSCO’s existing electric generation, but, depending on the outcome of ongoing litigation and potential future changes to the rules, may impose certain operational limitations on other existing and new electric generation. Through the 2024 NIPSCO IRP process, we assessed that cost to electric customers would be approximately $675 million greater due to these rules.

We also continue to monitor evolving state policies related to GHG emissions. The Climate Solutions Now Act of 2022 requires Maryland to reduce GHG emissions by 60% by 2031 (from 2006 levels), and it requires the state to reach net zero emissions by 2045. The Maryland Department of the Environment ("MDE") adopted a plan to achieve its 2031 goal and is required to adopt a plan for their 2045 net zero goal by 2030. The Act also enacts a state policy to move to broader electrification of both existing buildings and new construction. In December 2024, the MDE issued updated final Building Energy Performance Standards, which would require net zero direct GHG emissions from large buildings by 2040 with interim targets, or payments of an alternative compliance fee. Columbia of Maryland is advocating for compliance pathways that use RNG, hydrogen, new technologies and emissions offsets. Under an executive order, Maryland is also developing a Clean Heat Standard and a Zero-Emission Heating Equipment Standard that are intended to transition gas appliances to electric heat pumps. Separately, the PSC has also initiated a proceeding related to Near-Term, Priority Actions and Comprehensive, Long-Term Planning for Maryland's Gas Companies. Columbia of Maryland cannot predict the final impact of these policies on our business at this time.

Net Zero Goal. In November 2022, we announced a goal of net zero GHG emissions by 2040 covering both Scope 1 and Scope 2 GHG emissions ("Net Zero Goal"). Our Net Zero Goal builds on GHG emission reductions achieved to-date. We plan to achieve our Net Zero Goal primarily through continuation and enhancement of existing programs, such as retiring and replacing coal-fired electric generation with low- or zero-emission electric generation, ongoing pipe replacement and modernization programs, and deployment of advanced leak-detection technologies. In addition, we plan to advance other low- and zero-emission energy resources and technologies, which may include hydrogen, renewable natural gas, long-duration storage, and/or deployment of carbon capture and utilization technologies, if and when these become technologically and economically feasible. Carbon offsets and renewable energy credits may also be used to support achievement of our Net Zero Goal. As of the end of 2024, we had reduced Scope 1 GHG emissions by approximately 72% from 2005 levels.

Our GHG emissions projections, including achieving a Net Zero Goal, are subject to various assumptions that involve risks and uncertainties, and did not include any assumptions related to data center development and associated load growth. We remain committed to our Net Zero Goal, however, certain of our interim goals may evolve as we assess and respond to business opportunities such as data centers. Achievement of our Net Zero Goal by 2040 will require supportive regulatory and legislative policies, favorable stakeholder environments and advancement of technologies that are not currently economically or technologically feasible to deploy at scale, as well as execution of our business plan. Otherwise, our actual results or ability to achieve our Net Zero Goal, including by 2040, may differ materially.