Florida mice are mostly nocturnal but may be active during daytime as well. They prefer wooded, shrubby areas but also invade garages, sheds, and homes. Florida mice are solitary and territorial, with home ranges of 0.1 to 0.25 acres (0.04 to 0.1 hectares).
Their nests are globular, 8 to 10 inches (20 to 25 cm) in diameter, and built either underground or under debris on the surface. Nests are lined with grasses, stems, Spanish moss, and shredded palmetto fronds. Florida mice occasionally climb but mostly forage on the ground, digging for seeds and insects.