Lake Ontario, New York

4,656,925 acres

Surface Area

245 ft

Surface Elevation

Where It Sits, and How Deep It Goes

Locator - New York

43.66 degrees N, 77.76 degrees W - Jefferson County. State and county outlines drawn from Census boundary data; the lake marker is placed by its New York State DEC coordinates, not by eye. Schematic - not a survey map.

How Lake Ontario Stacks Up

Ranks #2 for surface area among the New York lakes counted so far - 4,656,925 acres.
The largest lake in Jefferson County among those counted.
About 36 miles from Rochester, as the crow flies.

Facts and Figures

Waterbody ID152712037

CountyJefferson

Coordinates43.6630, -77.7646

Deepest Natural Lakes in New York

#	Lake	County	Surface Area	Max Depth
1	Seneca Lake	Ontario, Yates, Seneca, Schuyler	43,343 acres	618 ft
2	Cayuga Lake	Cayuga	42,956 acres	435 ft
3	Skaneateles Lake	Onondaga, Cortland, Cayuga	8,960 acres	300 ft
4	Canandaigua Lake	Ontario, Yates	10,558 acres	276 ft
5	Lake George	Essex, Warren	28,451 acres	187 ft

Largest Lakes in New York

#	Lake	County	Surface Area	Max Depth
1	Lake Erie	Erie	6,360,010 acres	-
2	Lake Ontario	Jefferson	4,656,925 acres	-
3	Lake Champlain	Washington	277,117 acres	-
4	Oneida Lake	Oswego	51,324 acres	-
5	Seneca Lake	Ontario, Yates, Seneca, Schuyler	43,343 acres	618 ft

Sources: USGS National Hydrography Dataset via NYS GIS lake data (ID 152712037). Verified October 30, 2026.