31 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Portland | 1 | 70,104 | 68,496 | 0.38% | 3,255 | 22 | City |
| Portland | 2 | 69,970 | 68,496 | 0.29% | 3,248 | 22 | City |
| South Portland | 3 | 27,200 | 26,581 | 0.38% | 2,258 | 12 | City |
| South Portland | 4 | 27,082 | 26,581 | 0.16% | 2,249 | 12 | City |
| Scarborough | 5 | 24,450 | 22,245 | 0.91% | 512 | 48 | Town |
| Westbrook | 6 | 22,772 | 20,435 | 3.14% | 1,325 | 17 | City |
| Brunswick | 7 | 22,751 | 21,763 | 0.26% | 486 | 47 | Town |
| Westbrook | 8 | 21,861 | 20,435 | 1.1% | 1,272 | 17 | City |
| Windham | 9 | 20,218 | 18,491 | 1.32% | 434 | 47 | Town |
| Gorham | 10 | 18,637 | 18,364 | 0.25% | 368 | 51 | Town |
| Falmouth | 11 | 12,931 | 12,475 | 0.05% | 440 | 29 | Town |
| Standish | 12 | 11,125 | 10,241 | 1.04% | 188 | 59 | Town |
| Cape Elizabeth | 13 | 9,820 | 9,539 | 0.68% | 661 | 15 | Town |
| Yarmouth | 14 | 9,076 | 8,998 | 0.09% | 677 | 13 | Town |
| Freeport | 15 | 8,993 | 8,741 | 0.65% | 259 | 35 | Town |
| Cumberland | 16 | 8,958 | 8,469 | 0.71% | 392 | 23 | Town |
| Gray | 17 | 8,867 | 8,287 | 1.63% | 205 | 43 | Town |
| Bridgton | 18 | 6,256 | 5,423 | 2.96% | 110 | 57 | Town |
| New Gloucester | 19 | 5,997 | 5,690 | 1.15% | 127 | 47 | Town |
| Harpswell | 20 | 5,110 | 5,023 | 0.35% | 212 | 24 | Town |
| Raymond | 21 | 4,736 | 4,556 | 0.79% | 143 | 33 | Town |
| North Yarmouth | 22 | 4,438 | 4,099 | 0.86% | 209 | 21 | Town |
| Naples | 23 | 4,186 | 3,926 | 1.5% | 131 | 32 | Town |
| Casco | 24 | 3,813 | 3,642 | 0.95% | 122 | 31 | Town |
| Harrison | 25 | 2,672 | 2,455 | 1.6% | 80 | 33 | Town |
| Sebago | 26 | 2,009 | 1,913 | 1.01% | 61 | 33 | Town |
| Baldwin | 27 | 1,703 | 1,520 | 2.28% | 48 | 35 | Town |
| Pownal | 28 | 1,674 | 1,574 | 1.52% | 73 | 23 | Town |
| Chebeague Island | 29 | 405 | 397 | 0.5% | 113 | 4 | Town |
| Long Island | 30 | 231 | 235 | -0.43% | 161 | 1 | Town |
| Frye Island | 31 | 31 | 28 | 3.33% | 23 | 1 | Town |
Portland is the largest city in Cumberland County, with a population of 70,104.
Frye Island is the smallest city in Cumberland County, with a population of 31.
There are 31 cities in Cumberland County, Maine.