We estimate the impact of bank merger announcements on borrowers' stock prices for publicly traded Norwegian firms. In addition, we analyze how bank mergers influence borrower relationship termination behavior and relate the propensity to terminate to borrower abnormal returns. We obtain four main results. First, on average borrowers lose about 1 percent in equity value when their bank is announced as a merger target. Small borrowers of target banks are especially hurt in mergers between two large banks, where they lose an average of about 3 percent. Small target borrowers are not harmed, and appear to even gain, from mergers between small banks. Second, bank mergers lead to higher relationship exit rates for three years after a bank merger, and small bank mergers lead to larger increases in exit rates than large mergers. Third, target borrower abnormal returns are positively related to pre-merger exit rates, indicating that firms that find it easier to switch banks are less harmed when their bank merges. Fourth, we find weak evidence that target borrowers with large merger-induced increases in exit rates are more negatively affected by bank merger announcements, suggesting that target borrowers can be forced out of relationships and suffer welfare losses as a result of bank mergers.