We study whether competition affects banks' liquidity risk‐taking, which was at the heart of the 2008 financial crisis. We find that banks with greater market power take more liquidity risk, implying that decreased competition leads to financial fragility. During a financial crisis, however, the effect of market power on liquidity risk varies across bank size. Small banks with greater market power reduce liquidity risk while large banks with greater market power do not change their liquidity risk‐taking behavior. This suggests that enhanced charter values due to reduced competition lowers small banks' risk‐shifting incentives when their default risk significantly increases during a crisis. (JEL G21, G28)