Despite more than 150 years of research, to date a concise summary of the spatial distribution of Connecticut's freshwater fish fauna is lacking. Here we compile the spatial data assigned to more than a century's worth of collection efforts. Our survey summarizes specimen data previously deposited within 10 museums, comprising a total of 1305 specimen lots for 84 species. We assigned each lot to the township where it was collected, the first detailed summary of the distribution of Connecticut's freshwater fishes, with the ultimate goal of providing a framework for further local studies of freshwater fish conservation biology, ecology, evolution and management. Our records also reveal several populations not yet documented, including previously overlooked stickleback records that could have broader evolutionary implications.