Bank First Corp美股招股说明书(2026-08-03版)

MERGER PROPOSED — YOUR VOTE IS VERY IMPORTANT To the Shareholders of PSB Holdings, Inc.: The boards of directors of Bank First Corporation, or Bank First, and PSB Holdings, Inc., or PSB, have each unanimouslyapproved the acquisition of PSB by Bank First. The acquisition will be accomplished pursuant to the terms of an Agreement andPlan of Merger, dated as of May19, 2026, which we refer to as the merger agreement, by and between Bank First and PSB,whereby PSB will be merged with and into Bank First, which we refer to as the merger. Immediately following the merger of PSB with and into Bank First, Peoples State Bank, a wholly owned bank subsidiary ofPSB, will merge with and into Bank First’s wholly owned bank subsidiary, Bank First, N.A., with Bank First, N.A. as thesurviving bank, which we refer to as the bank merger. Unless otherwise indicated or the context otherwise requires, references in this letter to “PSB shareholders” are to holdersof PSB common stock. Holders of PSB preferred stock are addressed separately where applicable. If the merger is completed, each share of PSB common stock issued and outstanding immediately prior to the effective timeof the merger will be converted into the right to receive 0.3470 of a share (the “exchange ratio”) of Bank First common stock,with cash paid in lieu of fractional shares (the “merger consideration”). Notwithstanding the foregoing, the merger considerationis subject to a downward adjustment if PSB’s tangible book value (as calculated per the merger agreement) is less than$122,837,000 at the time of the closing of the merger. Additionally, each holder of PSB preferred stock has entered into a preferred stock redemption agreement with PSB andBank First, pursuant to which, immediately prior to the effective time of the merger, each holder will sell all of such holder’sshares of PSB preferred stock to PSB. As consideration for such sale, Bank First will deliver to each holder a promissory note inan original principal amount equal to the number of shares of PSB preferred stock held by such holder multiplied by $1,000 pershare, bearing interest at the fixed rate of 8.83% per annum and maturing on October1, 2027. In connection with suchagreement, each holder of PSB preferred stock has also agreed to vote in favor of the merger agreement and the transactionscontemplated therein. Although the number of shares of Bank First common stock that PSB shareholders will receive is fixed, the market value ofthe merger consideration will fluctuate with the market price of Bank First common stock and will not be known at the time PSBshareholders vote on the merger. Bank First common stock is currently quoted on the Nasdaq Capital Market under the symbol“BFC.” On May18, 2026, the last full trading day before the public announcement of the merger agreement, based on the lastreported sale price of Bank First common stock of $143.66 per share, the exchange ratio represented approximately $49.85 invalue for each share of PSB common stock to be converted into Bank First common stock. PSB common stock is traded on theOTCQX Market under the symbol “PSBQ”, and the last reported sale price of a PSB share on May 18, 2026, the last full tradingdate before the merger announcement, was $27.60 per share. At the May 19, 2026 announcement date, the $49.85 PSB mergervalue represented an 80.6% increase from the last reported sale price of a PSB share on May 18, 2026. Based on the closing saleprice of Bank First common stock of $151.78 per share on July29, 2026, the latest practicable trading date prior to the printingof this proxy statement/prospectus, the exchange ratio represented approximately $52.67 in value for each share of PSB commonstock to be converted into Bank First common stock. The most recent reported closing sale price of PSB common stock onJuly29, 2026 was $50.67.We urge you to obtain current market quotations for the price of Bank First common stock (tradingsymbol “BFC”) and PSB common stock (trading symbol “PSBQ”) because the value of the merger consideration will fluctuate basedon Bank First’s common stock price. PSB will hold a special meeting of its shareholders, referred to as the PSB special meeting, where PSB shareholders will beasked to consider and vote upon (1)a proposal to approve the merger agreement and the merger, and (2)a proposal to adjourn the PSB special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the mergeragreement and the merger. The PSB special meeting will be held on September2, 2026, at 2:00p.m., Central Time, at Rib River by Accentu, Inc.,135737 State Hwy 29, Marathon City, Wisconsin, subject to any adjournment or postponement thereof. Each of Bank First and PSB expects that the merger will qualify as a “reorganization” within the meaning of Section368(a)of the Internal Revenue Code of 1986, as amended, which we refer to as the Code, with the result that PSB common stockexchanged for Bank