Lakes / Montana / Rattlesnake Reservoir
Rattlesnake Reservoir, Montana
183.8 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Montana
45.90 degrees N, 108.43 degrees W - Yellowstone County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Montana Fish, Wildlife & Parks coordinates, not by eye. Schematic - not a survey map.
How Rattlesnake Reservoir Stacks Up
- The largest lake in Yellowstone County among those counted.
- About 9 miles from Billings, as the crow flies.
Facts and Figures
Waterbody ID142618429
CountyYellowstone
Coordinates45.9009, -108.4285
Largest Lakes in Montana
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Fort Peck Lake | Valley | 233,053 acres | - |
| 2 | Flathead Lake | Lake | 122,132 acres | About 380 ft |
| 3 | Canyon Ferry Lake | Broadwater | 32,773 acres | About 170 ft |
| 4 | Lake Koocanusa | Lincoln | 28,723 acres | - |
| 5 | Hungry Horse Reservoir | Flathead | 23,577 acres | - |
Sources: USGS NHD lake data (ID 142618429). Verified October 30, 2026.