59 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bangor | 1 | 32,538 | 31,720 | 0.14% | 950 | 34 | City |
| Orono | 2 | 12,217 | 11,169 | 0.07% | 672 | 18 | Town |
| Brewer | 3 | 9,553 | 9,669 | -0.4% | 627 | 15 | City |
| Hampden | 4 | 8,076 | 7,735 | 0.34% | 213 | 38 | Town |
| Old Town | 5 | 7,617 | 7,431 | 0.7% | 196 | 39 | City |
| Hermon | 6 | 7,051 | 6,483 | 0.93% | 197 | 36 | Town |
| Lincoln | 7 | 4,971 | 4,847 | 0.26% | 73 | 68 | Town |
| Glenburn | 8 | 4,805 | 4,652 | 0.21% | 177 | 27 | Town |
| Millinocket | 9 | 4,102 | 4,108 | -0.17% | 258 | 16 | Town |
| Orrington | 10 | 3,929 | 3,812 | 0.43% | 157 | 25 | Town |
| Dexter | 11 | 3,887 | 3,801 | 0.49% | 111 | 35 | Town |
| Holden | 12 | 3,426 | 3,282 | 0.2% | 109 | 31 | Town |
| Levant | 13 | 3,237 | 2,939 | 0.53% | 108 | 30 | Town |
| Corinth | 14 | 3,202 | 2,902 | 1.91% | 80 | 40 | Town |
| Newport | 15 | 3,171 | 3,126 | 0.19% | 107 | 30 | Town |
| Milford | 16 | 3,104 | 3,068 | -0.06% | 68 | 46 | Town |
| Carmel | 17 | 3,047 | 2,870 | 0.79% | 83 | 37 | Town |
| Eddington | 18 | 2,276 | 2,187 | 0.09% | 91 | 25 | Town |
| Corinna | 19 | 2,260 | 2,217 | 0.18% | 58 | 39 | Town |
| Veazie | 20 | 1,882 | 1,815 | 1.02% | 622 | 3 | Town |
| Newburgh | 21 | 1,793 | 1,604 | 2.11% | 58 | 31 | Town |
| Charleston | 22 | 1,659 | 1,551 | 1.16% | 41 | 41 | Town |
| Greenbush | 23 | 1,580 | 1,446 | 2.13% | 36 | 44 | Town |
| Bradley | 24 | 1,570 | 1,529 | 0.13% | 32 | 50 | Town |
| East Millinocket | 25 | 1,560 | 1,568 | -0.19% | 220 | 7 | Town |
| Hudson | 26 | 1,472 | 1,417 | 0.82% | 39 | 38 | Town |
| Enfield | 27 | 1,441 | 1,430 | -0.07% | 52 | 28 | Town |
| Kenduskeag | 28 | 1,420 | 1,345 | 0.35% | 85 | 17 | Town |
| Plymouth | 29 | 1,311 | 1,325 | -0.46% | 44 | 30 | Town |
| Bradford | 30 | 1,251 | 1,179 | 1.05% | 30 | 41 | Town |
| Stetson | 31 | 1,241 | 1,189 | 0.65% | 35 | 35 | Town |
| Etna | 32 | 1,236 | 1,227 | -0.08% | 50 | 25 | Town |
| Dixmont | 33 | 1,202 | 1,210 | -0.33% | 33 | 36 | Town |
| Medway | 34 | 1,186 | 1,186 | -0.25% | 29 | 41 | Town |
| Howland | 35 | 1,172 | 1,098 | 0.34% | 34 | 35 | Town |
| Garland | 36 | 1,029 | 1,021 | -0.1% | 27 | 38 | Town |
| Exeter | 37 | 1,000 | 964 | 0.4% | 26 | 39 | Town |
| Lee | 38 | 919 | 918 | 0% | 24 | 39 | Town |
| Patten | 39 | 896 | 882 | 0.11% | 23 | 38 | Town |
| Clifton | 40 | 883 | 846 | 0.57% | 26 | 35 | Town |
| Alton | 41 | 829 | 828 | -0.24% | 20 | 42 | Town |
| Lagrange | 42 | 641 | 635 | 0% | 13 | 49 | Town |
| Mattawamkeag | 43 | 606 | 595 | 0.17% | 16 | 38 | Town |
| Chester | 44 | 550 | 547 | -0.18% | 12 | 46 | Town |
| Burlington | 45 | 455 | 381 | 2.25% | 8 | 54 | Town |
| Springfield | 46 | 409 | 297 | 5.41% | 11 | 38 | Town |
| Winn | 47 | 407 | 399 | 0.25% | 9 | 44 | Town |
| Lowell | 48 | 385 | 366 | 0.26% | 10 | 38 | Town |
| Penobscot Indian Island Reservation | 49 | 378 | 370 | 0.27% | 50 | 8 | Township |
| Stacyville | 50 | 372 | 374 | -0.27% | 9 | 40 | Town |
| Passadumkeag | 51 | 354 | 354 | -0.28% | 15 | 23 | Town |
| Woodville | 52 | 203 | 203 | 0% | 5 | 43 | Town |
| Mount Chase | 53 | 188 | 187 | 0% | 5 | 37 | Town |
| Carroll | 54 | 136 | 137 | -0.73% | 3 | 44 | Plantation |
| Edinburg | 55 | 133 | 131 | 0% | 4 | 35 | Town |
| Maxfield | 56 | 106 | 80 | 8.16% | 6 | 19 | Town |
| Lakeville | 57 | 102 | 104 | -0.97% | 2 | 58 | Town |
| Webster | 58 | 64 | 65 | -1.54% | 2 | 37 | Plantation |
| Seboeis | 59 | 42 | 39 | 2.44% | 1 | 40 | Plantation |
Bangor is the largest city in Penobscot County, with a population of 32,538.
Seboeis is the smallest city in Penobscot County, with a population of 42.
There are 59 cities in Penobscot County, Maine.