As announced, the purchase and assumption agreement provided for First Interstate Bank to transfer the branch facilities and associated assets to Enterprise Bank & Trust along with approximately $740 million in deposits and roughly $200 million of outstanding loans, described as mostly commercially-oriented. No purchase price, deposit premium, or other valuation metric for the transaction was disclosed in any of the filings reviewed; the agreement was a branch/deposit purchase rather than a stock-for-stock or cash-per-share merger, and the companies did not publish an aggregate deal value, premium percentage, or multiple.
James B. Lally, President and CEO of Enterprise Financial Services Corp, said at announcement: "We are pleased to enter into this agreement with First Interstate Bank. This is a unique and strategically-aligned opportunity to expand our access to markets with both attractive growth opportunities and familiarity and to continue to generate long-term value for our shareholders. Since entering the Arizona market nearly fifteen years ago, we have grown our business significantly... In addition, we are also very excited to solidify our presence in Kansas City through this transaction." James A. Reuter, President and CEO of First Interstate BancSystem and First Interstate Bank, stated: "This agreement provides us an opportunity to shift our capital investment and drive growth in areas where we enjoy increased market share, while creating additional capital flexibility." On a pro forma basis at announcement, Enterprise expected the deal to expand its Arizona footprint to twelve full-service branches with approximately $1.3 billion of deposits, and to increase its greater Kansas City presence to nine full-service branches with approximately $1.1 billion of deposits.
The transaction closed on October 10, 2025, roughly five and a half months after signing, consistent with the originally guided timeline of "early fourth quarter of 2025." Both companies confirmed the closing in Form 8-K filings dated October 14, 2025. At closing, the actual transferred balances differed from the amounts disclosed at signing: Enterprise Bank & Trust assumed approximately $645 million in deposits and purchased approximately $300 million of performing loans associated with the twelve branches, versus the roughly $740 million in deposits and $200 million in loans originally disclosed in April 2025. Following completion, Enterprise disclosed it had approximately $17 billion in total assets (versus approximately $16.1 billion as of June 30, 2025, per the closing press release), reflecting the added deposits, loans, and real estate. The branches were fully converted to Enterprise Bank & Trust branch offices effective as of 11:59 p.m. Central time on the closing date.
At the closing announcement, Lally stated: "We are pleased to announce the completion of the acquisition of twelve First Interstate Bank branches in Arizona and Kansas City. In addition to an enhanced funding profile, the addition of these branches allows us to expand our access to existing markets with attractive growth opportunities. We believe this transaction will help us meet the needs of our new and existing customers while delivering continued long-term value for our stockholders."
No synergy dollar figures, cost-base percentage targets, EPS accretion/dilution estimates, tangible book value earnback period, or pro forma leverage figures were disclosed in any of the filings reviewed for this transaction. The filings also do not disclose a termination fee or detailed closing conditions beyond "regulatory approvals and other customary conditions of closing." No merger proxy, S-4, or investor presentation specific to this branch transaction was identified; the deal was announced and closed solely via joint press releases filed as 8-K exhibits by both companies.
Janney Montgomery Scott LLC acted as financial advisor and Holland & Knight LLP as legal advisor to Enterprise on the transaction. Keefe, Bruyette and Woods Inc. acted as financial advisor and Luse Gorman, PC as legal advisor to First Interstate. These advisor roles were confirmed in both the April 28, 2025 announcement press release and reiterated for Enterprise in the October 14, 2025 closing press release.