FIRST BUSINESS FINANCIAL SERVICES, INC. Debt Disclosure

As of December 31, 2025 the Corporation had a $791.1 million FHLB line of credit available for advances which is collateralized as noted below, of which $529.5 million remained unused. There were $197.2 million of term FHLB advances outstanding at December 31, 2025 with stated fixed interest rates ranging from 2.09% to 4.95% compared to $265.4 million of term FHLB advances outstanding at December 31, 2024 with stated fixed interest rates ranging from 1.19% to 4.95%. The term FHLB advances outstanding at December 31, 2025 are due at various dates through December 2031.

The Corporation is required to maintain as collateral mortgage-related securities, unencumbered first mortgage loans and secured small business loans in its portfolio aggregating at least the amount of outstanding advances from the FHLB. Loans totaling approximately $1.443 billion and $1.298 billion were pledged as collateral at December 31, 2025 and 2024, respectively.

The Corporation has a senior line of credit with a third-party financial institution of $10.5 million. As of December 31, 2025, the line of credit carried an interest rate of SOFR + 2.36% that matured on February 19, 2026 and had certain performance debt covenants of which the Corporation was in compliance. The Corporation pays a commitment fee on this senior line of credit. For the years ended December 31, 2025, 2024, and 2023 the Corporation incurred $13,000 additional interest expense due to this fee. There was no outstanding balance on the line of credit as of December 31, 2025. On February 18, 2026, the credit line was renewed for one additional year with pricing terms of 1-month term SOFR + 2.36% and a maturity date of February 17, 2027.

The Corporation issued subordinated notes payable on September 13, 2024. The aggregate principal amount of the newly issued subordinated notes payable was $20.0 million which qualified as Tier 2 capital. The subordinated notes payable bear a fixed interest rate of 7.5% with a maturity date of September 13, 2034. The Corporation may, at its option, redeem the notes payable, in whole or part, at anytime after the fifth anniversary of the issuance. As of August 15, 2024, the $15.0 million subordinated notes payable that bore a fixed interest rate of 5.5% were redeemed, and the remaining unamortized debt issuance cost was accelerated due to the early redemption. As of December 31, 2025, $195,000 of debt issuance costs remain in the subordinated note and debentures payable balance, of which $44,000 is related to the recently issued subordinated debentures.

The Corporation has entered into derivative contracts hedging a portion of the borrowings included in the 2026 maturities above. As of December 31, 2025, the notional amount of derivatives designated as cash flow hedges totaled $48.4 million with a weighted average remaining maturity of 2.12 years and a weighted average rate of 2.52%.