| City | County | 2026 Pop. ↓ |
|---|---|---|
| Rockland | Knox County | 7,240 |
| Rumford | Oxford County | 6,107 |
| Raymond | Cumberland County | 4,670 |
| Richmond | Sagadahoc County | 3,626 |
| Rockport | Knox County | 3,616 |
| Readfield | Kennebec County | 2,748 |
| Randolph | Kennebec County | 1,782 |
| Rangeley | Franklin County | 1,353 |
| Rome | Kennebec County | 1,186 |
| Robbinston | Washington County | 552 |
| Ripley | Somerset County | 488 |
| Roxbury | Oxford County | 364 |
| Roque Bluffs | Washington County | 318 |
| Rangeley | Franklin County | 178 |
| Reed | Aroostook County | 126 |