Locally abundant in California, inhabiting rocky or gravelly slopes with low to moderate shrub cover. Seeds are stored in abundance in burrow as well as in other places within the territory. Burrow excavated at the base of a bush. Underground nest of dried grasses and other plant parts is constructed in burrow.
Water is obtained metabolically from green vegetation and seeds, and from moisture in food.
Suitable habitat for Bailey's pocket mouse includes scrub flats or slopes. Agricultural uses preclude its existence. Yearlong activity, although individuals may become torpid over short periods during high summer temperatures. Pocket mice are aggressively solitary. Territory size unknown but probably equal to home range.