The Bedford springsnail (Pyrgulopsis bedfordensis) is one of only 2 species of the genus Pyrgulopsis discovered east of the northern Continental Divide and appears restricted to one spring in central Montana. Due to its endemism, this species was placed on the Montana Species of Concern list as S1, critically imperiled. Despite the snail's rarity, nothing was known of this population's characteristics; it was last sampled in 1999. In 2015, I quantitatively sampled this population using a Hess sampler (n = 3) over a 40-m reach to determine the snail's benthic density and describe the associated macroinvertebrate community. Average densities of the springsnail were 30,540 live individuals per m² (SE 2625) and 17,353 empty shells per m² (SE 1389). Other benthic macroinvertebrates collected with the springsnail (11 taxa [SE 1.5]) were comparatively low in abundance, averaging 1533 individuals per m² (SE 274). The Bedford springsnail population density at this Montana site ranks among one of the highest reported among its conspecifics.