Founded in 1827, Waldo County is one of 16 counties in the state of Maine. Historically, Waldo County was formed from parts of Hancock County, Kennebec County and Lincoln County. The city of Belfast is the county seat. With FIPS code of 27, Waldo County has a population of 39,912 and area of 853 square miles (2,209 km2).
List of all cities in Waldo County, ME alphabetically
| City/Town | Postal Code | Area Code |
| Belfast, ME | 04915 | 207 |
| Belmont, ME | 04952 | 207 |
| Brooks, ME | 04921 | 207 |
| Burnham, ME | 04922 | 207 |
| Frankfort, ME | 04438 | 207 |
| Freedom, ME | 04941 | 207 |
| Islesboro, ME | 04848 | 207 |
| Jackson, ME | 04921 | 207 |
| Knox, ME | 04986 | 207 |
| Liberty, ME | 04949 | 207 |
| Lincolnville, ME | 04849 | 207 |
| Lincolnville Center, ME | 04850 | 207 |
| Monroe, ME | 04951 | 207 |
| Montville, ME | 04941 | 207 |
| Morrill, ME | 04952 | 207 |
| Northport, ME | 04849 | 207 |
| Palermo, ME | 04354 | 207 |
| Prospect, ME | 04981 | 207 |
| Sandy Point, ME | 04972 | 207 |
| Searsmont, ME | 04973 | 207 |
| Searsport, ME | 04974 | 207 |
| Stockton Springs, ME | 04981 | 207 |
| Swanville, ME | 04915 | 207 |
| Thorndike, ME | 04986 | 207 |
| Troy, ME | 04987 | 207 |
| Unity, ME | 04988 | 207 |
| Waldo, ME | 04915 | 207 |
| Winterport, ME | 04496 | 207 |