FIBK

Business Context and Reporting Period

Company: First Interstate BancSystem, Inc. (FIBK)
Filing Type: Form 8-K (Current Report)
Date of Report: June 10, 2025
Event: Completion of a public offering of $125,000,000 aggregate principal amount of 7.625% Fixed-to-Floating Rate Subordinated Notes due 2035.

Key Financial Metrics and Debt Structure

Debt Issuance: $125,000,000 in Subordinated Notes.
Capital Classification: Treated as Tier 2 capital for regulatory purposes.
Interest Rate Structure:

• Fixed Period (Issuance to June 15, 2030): 7.625% per annum, payable semi-annually.
• Floating Period (June 15, 2030 to Maturity): Three-Month Term SOFR + 398.0 basis points, payable quarterly.

Subordination: Unsecured and subordinated to all senior indebtedness; structurally subordinated to liabilities of the bank subsidiary, First Interstate Bank.

Material Changes and Terms

The filing details the entry into a material definitive agreement (Second Supplemental Indenture) to issue the Notes. Key terms include:

• Redemption: The Company may redeem the Notes in whole or in part beginning June 15, 2030. Full redemption is permitted upon a "Tax Event" or "Tier 2 Capital Event."
• Acceleration: Maturity may only be accelerated upon bankruptcy or insolvency events of the Company or its bank subsidiary. There is no right of acceleration for payment defaults.
• Payment Commencement: First interest payment due December 15, 2025.

Guidance, Outlook, and Risks

Management Commentary: The filing confirms the successful completion of the offering previously announced by the Company. The proceeds are intended to support the Company's capital position as Tier 2 capital.
Risks and Contingencies:

• Early redemption is subject to Federal Reserve Board approval where required by capital regulations.
• The Notes are structurally subordinated to the liabilities of the Company's subsidiaries, including deposit liabilities.
• Interest rates post-2030 are variable and dependent on the Three-Month Term SOFR benchmark.

Unusual Items: None reported in this filing.

Investor Verification Checklist

• Verify the impact of the $125 million issuance on the Company's total leverage and capital adequacy ratios.
• Review the full text of the Second Supplemental Indenture (Exhibit 4.2) for specific definitions of "Tax Event" and "Tier 2 Capital Event."
• Assess the Company's sensitivity to interest rate fluctuations post-June 2030 given the floating rate structure.
• Confirm the use of proceeds and whether the offering was fully subscribed.