Depositors maintain substantial, rate-insensitive account balances to facilitate payments and meet liquidity needs. Analyzing over 50 billion transactions from more than 1,400 U.S. banks, we find that, contrary to conventional wisdom, depositors actively manage their deposits and value payment convenience: faster settlement in deposit transfers increases gross deposit transfers between bank accounts while reducing total deposit balances. We extend the Baumol-Tobin framework with transfer delays to align with new empirical findings and quantify the impact of fast payments on depositor behavior. If banks uniformly adopt next-day settlement, ceteris paribus, low-interest precautionary and transactional deposits would decrease by approximately 30%, and related deposit transfer activities would increase by 40%. Our findings indicate that payment convenience significantly influences the sticky demand for deposits, which has important implications for deposit franchise value and monetary transmission.