27 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Belfast | 1 | 7,015 | 6,948 | 0.16% | 206 | 34 | City |
| Belfast | 2 | 6,987 | 6,948 | -0.04% | 205 | 34 | City |
| Winterport | 3 | 3,841 | 3,822 | -0.31% | 108 | 36 | Town |
| Searsport | 4 | 2,753 | 2,647 | 1.25% | 96 | 29 | Town |
| Lincolnville | 5 | 2,462 | 2,321 | 0.9% | 66 | 37 | Town |
| Unity | 6 | 2,342 | 2,288 | 0% | 59 | 39 | Town |
| Northport | 7 | 1,669 | 1,552 | 1.21% | 70 | 24 | Town |
| Palermo | 8 | 1,645 | 1,572 | 0.43% | 41 | 41 | Town |
| Stockton Springs | 9 | 1,590 | 1,541 | -0.06% | 81 | 20 | Town |
| Searsmont | 10 | 1,484 | 1,406 | 0.75% | 39 | 38 | Town |
| Swanville | 11 | 1,449 | 1,380 | 0.69% | 73 | 20 | Town |
| Frankfort | 12 | 1,240 | 1,232 | -0.24% | 50 | 25 | Town |
| Troy | 13 | 1,146 | 1,024 | 1.78% | 33 | 35 | Town |
| Burnham | 14 | 1,112 | 1,101 | -0.18% | 29 | 39 | Town |
| Morrill | 15 | 1,051 | 973 | 1.45% | 63 | 17 | Town |
| Montville | 16 | 1,023 | 1,020 | -0.29% | 24 | 43 | Town |
| Brooks | 17 | 1,020 | 1,009 | -0.2% | 41 | 25 | Town |
| Belmont | 18 | 1,015 | 981 | -0.29% | 75 | 14 | Town |
| Liberty | 19 | 941 | 936 | -0.32% | 36 | 26 | Town |
| Monroe | 20 | 937 | 931 | -0.32% | 24 | 39 | Town |
| Waldo | 21 | 874 | 798 | 1.27% | 45 | 19 | Town |
| Thorndike | 22 | 813 | 777 | 0.62% | 32 | 25 | Town |
| Knox | 23 | 807 | 808 | -0.25% | 28 | 29 | Town |
| Freedom | 24 | 754 | 711 | 1.48% | 35 | 22 | Town |
| Prospect | 25 | 707 | 697 | -0.14% | 39 | 18 | Town |
| Jackson | 26 | 610 | 610 | -0.49% | 24 | 25 | Town |
| Islesboro | 27 | 599 | 581 | 0.34% | 42 | 14 | Town |
Belfast is the largest city in Waldo County, with a population of 7,015.
Islesboro is the smallest city in Waldo County, with a population of 599.
There are 27 cities in Waldo County, Maine.