We document the importance of covenant violations in transmitting bank health to nonfinancial firms. Roughly one‐third of loans in our supervisory data breach a covenant during the 2008 to 2009 period, allowing lenders to force a renegotiation of loan terms or to accelerate repayment of otherwise long‐term credit. Lenders in worse health are more likely to force a reduction in the loan commitment following a violation. The reduction in credit to borrowers who violate a covenant can account for the majority of the cross‐sectional variation in credit supply during the 2008 to 2009 crisis.

We use supervisory loan-level data to document that small firms (SMEs) obtain shorter maturity credit lines than large firms, post more collateral, have higher utilization rates, and pay higher spreads. We rationalize these facts as the equilibrium outcome of a trade-off between lender commitment and discretion. Using the COVID recession, we test the prediction that SMEs are subject to greater lender discretion. Consistent with this hypothesis, SMEs did not draw down whereas large firms did, even in response to similar demand shocks. PPP recipients reduced non-PPP loan balances, indicating the program bolstered their liquidity and alleviated the shortfall.