A pollen-storer. Females establish their nests on or at various depths below the ground (Løken, 1973). On South Uist, Western Isles, Wild (1931) found two nests on the surface of the ground and three below; one of the latter was approached by a tunnel about 0.75 metre long. These nests had an outer covering of moss; the wax was bright orange in colour and rather scanty in amount. Unusual nest sites include an abandoned squirrel's drey in the top of a pine tree (Sladen, 1912) and a vacated bird's nest (Fraser, 1947). Colonies are generally small. Meidell (in Løken, 1973) estimated the maximum number of workers produced in a Scandinavian nest as about thirty individuals. An occupied nest is illustrated by E. von Hagens (1986).
This species has been observed establishing in abandoned Sciurus vulgaris nests (Sladen, 1912). Rasmont (2008) reports that the species may occasionally occupy abandoned bird's nests.