The largest county in Wyoming
There are two right answers. By land area it is Sweetwater County; by population it is Laramie County. Which one you want depends on what you meant by largest.
Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025. Retrieved 30 August 2026.
By land area
| Rank | Name | Land area | Population |
|---|---|---|---|
| 1 | Sweetwater County | 10,427 sq mi | 41,267 |
| 2 | Fremont County | 9,184 sq mi | 39,464 |
| 3 | Carbon County | 7,898 sq mi | 14,013 |
| 4 | Park County | 6,939 sq mi | 31,171 |
| 5 | Natrona County | 5,341 sq mi | 80,526 |
| 6 | Sublette County | 4,886 sq mi | 8,929 |
| 7 | Campbell County | 4,802 sq mi | 48,145 |
| 8 | Albany County | 4,274 sq mi | 38,558 |
| 9 | Converse County | 4,255 sq mi | 13,824 |
| 10 | Johnson County | 4,154 sq mi | 8,908 |
By population
| Rank | Name | Population | Density |
|---|---|---|---|
| 1 | Laramie County | 102,938 | 38.3 per sq mi |
| 2 | Natrona County | 80,526 | 15.1 per sq mi |
| 3 | Campbell County | 48,145 | 10.0 per sq mi |
| 4 | Sweetwater County | 41,267 | 4.0 per sq mi |
| 5 | Fremont County | 39,464 | 4.3 per sq mi |
| 6 | Albany County | 38,558 | 9.0 per sq mi |
| 7 | Sheridan County | 33,241 | 13.2 per sq mi |
| 8 | Park County | 31,171 | 4.5 per sq mi |
| 9 | Teton County | 23,333 | 5.8 per sq mi |
| 10 | Lincoln County | 21,180 | 5.2 per sq mi |
And the smallest
More on Wyoming
Rebuilt from source data 30 August 2026. How these figures are produced.