Lakes / Illinois / Mason County / Jack Lake
Jack Lake, Illinois
1,500.58 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Illinois
40.18 degrees N, 90.18 degrees W - Mason County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Jack Lake Stacks Up
- Larger than 94% of the 511 lakes counted in Illinois.
- About 39 miles from Springfield, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Moscow Lake | Mason | 1.0 mi | 249.33 acres |
| Stickey Lake | Fulton | 1.5 mi | 1,401 acres |
| Patterson Bay | Mason | 1.7 mi | 50.66 acres |
| Bell Lake | Fulton | 1.7 mi | 33.11 acres |
| Bath Lake | Mason | 2.9 mi | 149.75 acres |
| Chain Lake | Mason | 3.7 mi | 30.15 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Jack Lake
How Big Is Jack Lake?
Jack Lake covers 1,500.58 acres in Mason County, Illinois.
What Is the Largest Lake in Mason County?
Quiver Lake is the largest lake in Mason County, at 2,926.49 acres.
Largest Lakes in Illinois
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Carlyle Lake | Clinton | 22,796.77 acres | - |
| 2 | Mine Number 21 Reservoir | Franklin | 17,062.04 acres | - |
| 3 | Upper Peoria Lake | Woodford | 15,460.64 acres | - |
| 4 | Lake Shelbyville | Shelby | 10,235.1 acres | - |
| 5 | Crab Orchard Lake | Williamson | 7,292.57 acres | - |
All 511 Illinois lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 154319410). Verified October 30, 2026.