The largest county in Maine
There are two right answers. By land area it is Aroostook County; by population it is Cumberland 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 | Aroostook County | 6,671 sq mi | 66,609 |
| 2 | Piscataquis County | 3,961 sq mi | 17,409 |
| 3 | Somerset County | 3,924 sq mi | 51,620 |
| 4 | Penobscot County | 3,397 sq mi | 157,967 |
| 5 | Washington County | 2,563 sq mi | 31,334 |
| 6 | Oxford County | 2,077 sq mi | 60,346 |
| 7 | Franklin County | 1,697 sq mi | 30,824 |
| 8 | Hancock County | 1,587 sq mi | 57,171 |
| 9 | York County | 991.2 sq mi | 222,434 |
| 10 | Kennebec County | 867.5 sq mi | 129,067 |
By population
| Rank | Name | Population | Density |
|---|---|---|---|
| 1 | Cumberland County | 317,222 | 379 per sq mi |
| 2 | York County | 222,434 | 224 per sq mi |
| 3 | Penobscot County | 157,967 | 46.5 per sq mi |
| 4 | Kennebec County | 129,067 | 149 per sq mi |
| 5 | Androscoggin County | 116,487 | 249 per sq mi |
| 6 | Aroostook County | 66,609 | 10.0 per sq mi |
| 7 | Oxford County | 60,346 | 29.1 per sq mi |
| 8 | Hancock County | 57,171 | 36.0 per sq mi |
| 9 | Somerset County | 51,620 | 13.2 per sq mi |
| 10 | Knox County | 41,117 | 113 per sq mi |
And the smallest
More on Maine
Rebuilt from source data 30 August 2026. How these figures are produced.