Most mammalian central neurons receive synaptic input over complicated dendritic arbors. Therefore, timing of synaptic information should vary with synapse location. However, I report that temporal summation at CA1 pyramidal somata does not depend on the location of synaptic input. This spatial normalization of temporal integration requires a dendritic hyperpolarization-activated current (lh). Shaping of synaptic activity by deactivating a nonuniform lh could counterbalance filtering by dendrites and effectively remove location-dependent variability in temporal integration, thus enhancing synchronization of neuronal populations and functional capabilities of the hippocampal CA1 region.