Bats are facing threats from disease, wind power development, and climate change, which are causing populations of many species to decline. The northern range limits of many temperate species are not well characterized, but the true distribution of threatened bat species is critical information for their conservation. We used passive acoustic monitoring and false-positive occupancy models to estimate the distributions of six species of bats in northern Ontario (north of ca. 50.5°N). We confirmed the presence of big brown bats (Eptesicus fuscus), hoary bats (Lasiurus cinereus), eastern red bats (Lasiurus borealis), silver-haired bats (Lasionycteris noctivagans), little brown myotis (Myotis lucifugus), northern long-eared myotis (Myotis septentrionalis), and tri-colored bats (Perimyotis subflavus) in our study area. We found that big brown bats, hoary bats, and little brown myotis likely are more widespread and common in northern Ontario than previously thought. Our models also provided evidence of associations between temperature and habitat types and bat occupancy probabilities. Our occupancy probability maps for each species support bat conservation by providing much finer-scale distribution information than previously available. These results provide a much-needed baseline for future studies of the distribution of these bat species in northern Ontario against which to measure the effects of white-nose syndrome, resource development, and climate change.