Neuronal spike times are essential for coding information. A subset of neurons often emits a series of action potentials and generate sequences of spikes. The spike times of neurons during a sequence are regulated at the millisecond level while preserving flexibility to generate diverse patterns in different sequences. Spike sequences are exemplified by memory replays during sharp wave–ripples (SWRs). Hippocampal pyramidal cells that are sequentially activated during behavior are reactivated in time-compressed manner during SWRs while animals are immobile or asleep. This replay of sequential activity has been believed to contribute to memory consolidation and navigational planning. However, the mechanism for such flexible modification of spike times remains unclear. In this study, we conducted in vivo whole-cell recordings simultaneously from up to three CA1 pyramidal cells and examined the membrane potential dynamics at the single-cell level. Neurons were transiently hyperpolarized tens of milliseconds before SWRs. The pre-SWR hyperpolarizations varied in magnitude across SWR events and individual neurons, and larger pre-SWR hyperpolarizations induced later spike times during SWRs. Thus, pre-SWR inhibition coordinates the sequential spike times of CA1 pyramidal cells and diversifies the repertoire of sequence patterns.