NiSource Inc. Files Preliminary Prospectus Supplement for Senior Notes Due 2032

Offering Overview

On November 2, 2026, NiSource Inc. filed a preliminary prospectus supplement (Form 424B5) pursuant to Rule 424(b)(5) under its shelf registration statement (File No. 333-291167) for an offering of Senior Notes due 2032.

Key Terms of the Offering

• Issuer: NiSource Inc.
• Security: % Senior Notes due 2032
• Principal Amount & Interest Rate: To be determined upon pricing.
• Interest Payments: Semi-annually in arrears, commencing in 2027.
• Ranking: Senior unsecured obligations ranking equally with all other existing and future senior unsecured indebtedness of NiSource Inc., and structurally subordinated to liabilities of subsidiaries.
• Optional Redemption: Redeemable at any time prior to the Par Call Date (one month prior to maturity) at a make-whole redemption price based on the Treasury Rate plus a specified spread, and thereafter at 100% of the principal amount, plus accrued interest.
• Special Redemption: Redeemable at 101% of principal plus accrued interest upon the occurrence of a Tax Credit Event.
• Joint Book-Running Managers: BMO Capital Markets, KeyBanc Capital Markets, Mizuho, and PNC Capital Markets LLC.

Use of Proceeds

Net proceeds from the offering will be used for general corporate purposes, including financing capital expenditures (including generation and transmission investments to support data center load growth in northern Indiana), working capital, and the repayment of existing indebtedness.