NISOURCE INC

8. Long-Term Debt

Our long-term debt as of December 31, 2024 and 2023 is as follows:

Details of our 2024 long-term debt related activity are summarized below:

•On March 14, 2024, we completed the issuance and sale of $650.0 million of 5.350% senior unsecured notes maturing in 2034, which resulted in approximately $642.6 million of net proceeds after discount and debt issuance costs.

•On May 16, 2024, we completed the issuance and sale of $500.0 million of 6.950% fixed-to-fixed reset rate junior subordinated notes maturing in 2054, which resulted in approximately $493.4 million of net proceeds after debt issuance costs. The subordinated notes bear interest (i) from and including May 16, 2024 to, but excluding, November 30, 2029 at a rate of 6.950% per annum and (ii) from and including November 30, 2029, during each five-year reset period at a rate per annum equal to the five-year U.S. treasury rate (determined as described in the prospectus supplement dated May 13, 2024, which was filed with the SEC on May 14, 2024) as of the then most recent reset interest determination date plus a spread of 2.451%, to be reset on each reset date. At our option, we may redeem some or all of the subordinated notes during specified periods, and upon the occurrence of certain ratings or tax events, all as described in the prospectus supplement. In accordance with terms of the subordinated notes, we have the right, from time to time, to defer the payment of interest on the outstanding subordinated notes on one or more occasions for up to ten consecutive years. In the event that we were to exercise such right to defer interest on the subordinated notes, we would not be able to pay cash dividends on the common stock during the periods in which such payments were deferred. The subordinated notes were issued pursuant to a Subordinated Indenture, dated as of May 16, 2024, between us and The Bank of New York Mellon, as trustee, as supplemented by the First Supplemental Indenture thereto, dated as of May 16, 2024.

•On June 24, 2024, we completed the issuance and sale of $600.0 million of 5.200% senior unsecured notes maturing in 2029, which resulted in approximately $593.7 million of net proceeds after discount and debt issuance costs.

•On September 9, 2024, we completed the issuance and sale of $500.0 million of 6.375% fixed-to-fixed reset rate junior subordinated notes maturing in 2055, which resulted in approximately $493.6 million of net proceeds after debt issuance costs. The subordinated notes bear interest (i) from and including September 9, 2024 to, but excluding, March 31, 2035 at a rate of 6.375% per annum and (ii) from and including March 31, 2035, during each five-year reset period at a rate per annum equal to the five-year U.S. treasury rate (determined as described in the prospectus supplement dated September 3, 2024, which was filed with the SEC on September 4, 2024) as of the then most recent reset interest determination date plus a spread of 2.527%, to be reset on each reset date. At our option, we may redeem some or all of the subordinated notes during specified periods, and upon the occurrence of certain ratings or tax events, all as described in the prospectus supplement. In accordance with terms of the subordinated notes, we have the right, from time to time, to defer the payment of interest on the outstanding subordinated notes on one or more occasions for up to ten consecutive years. In the event that we were to exercise such right to defer interest on the subordinated notes, we would not be able to pay cash dividends on the common stock during the periods in which such payments were deferred. The subordinated notes were issued pursuant to a Subordinated Indenture, dated as of May 16, 2024, between us and The Bank of New York Mellon, as trustee, as supplemented by the Second Supplemental Indenture thereto, dated as of September 9, 2024.

Details of our 2023 long-term debt related activity are summarized below:

•On March 24, 2023, we completed the issuance sale of $750.0 million of 5.250% senior unsecured notes maturing in 2028, which resulted in approximately $742.2 million of net proceeds after discount and debt issuance costs.

•On June 8, 2023, we completed the issuance and sale of $300.0 million of 5.250% senior unsecured notes maturing in 2028 (the "2028 Notes"). The terms of the 2028 Notes, other than the issue date and the price to the public, are identical to the terms of, and constitute as a reopening of, our 5.250% senior unsecured notes due 2028 issued on March 24, 2023. With the incremental issuance, we now have $1.05 billion of 5.250% senior unsecured notes maturing in 2028. On June 8, 2023, we also completed the issuance and sale of $450.0 million of 5.400% senior unsecured notes maturing in 2033. These issuances resulted in approximately $742.5 million of total net proceeds after discount and debt issuance costs.

See Note 19, "Other Commitments and Contingencies - A. Contractual Obligations," for the outstanding long-term debt maturities at December 31, 2024.

Unamortized debt expense, premium and discount on long-term debt applicable to outstanding bonds are being amortized over the life of such bonds.

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, 2024, the ratio was 52.6%.

We are also subject to certain other non-financial covenants under the revolving credit facility. Such covenants include a limitation on the creation or existence of new liens on our assets, generally exempting liens on utility assets, purchase money security interests, preexisting security interests and an additional subset of assets equal to $200 million. An asset sale covenant generally restricts the sale, conveyance, lease, transfer or other disposition of our assets to those dispositions that are for a price not materially less than fair market of such assets, that would not materially impair our ability to perform obligations under the revolving credit facility, and that together with all other such dispositions, would not have a material adverse effect. The covenant also restricts dispositions to no more than 15% of our consolidated total assets on December 31, 2022. Additionally, the revolving credit facility requires us to own directly or indirectly at least 70% of NIPSCO. The revolving credit facility also includes a cross-default provision, which triggers an event of default under the credit facility in the event of an uncured payment default relating to any indebtedness of us or any of our subsidiaries in a principal amount of $75.0 million or more.

Our indentures generally do not contain any financial maintenance covenants. However, our indentures are generally subject to cross-default provisions ranging from uncured payment defaults of $5.0 million to $50.0 million, and limitations on the incurrence of liens on our assets, generally exempting liens on utility assets, purchase money security interests, preexisting security interests and an additional subset of assets capped at 10% of our consolidated net tangible assets.