The Eastern ribbonsnake occurs east of the Mississippi River from Florida to southern Canada.
There are 4 recognized subspecies of the Eastern ribbonsnake. The only subspecies found in Canada is the Northern ribbonsnake (Thamnophis sauritus septentrionalis), which occurs in southern Ontario, southwestern Quebec and southwestern Nova Scotia. The main range of the Northern ribbonsnake is around the Great Lakes region of the United States and Canada where it occurs from southern Ontario and Michigan south to Illinois and east to Maine. Isolated populations exist in Nova Scotia and Wisconsin.