10 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Topsham | 1 | 9,976 | 9,565 | 0.79% | 310 | 32 | Town |
| Bath | 2 | 8,731 | 8,765 | -0.49% | 957 | 9 | City |
| Richmond | 3 | 3,559 | 3,523 | -0.2% | 117 | 30 | Town |
| Woolwich | 4 | 3,252 | 3,072 | 0.4% | 93 | 35 | Town |
| Bowdoin | 5 | 3,203 | 3,139 | -0.09% | 74 | 43 | Town |
| Bowdoinham | 6 | 3,190 | 3,062 | 0% | 93 | 34 | Town |
| Phippsburg | 7 | 2,200 | 2,156 | -0.09% | 76 | 29 | Town |
| West Bath | 8 | 1,955 | 1,911 | 0.1% | 164 | 12 | Town |
| Georgetown | 9 | 1,090 | 1,057 | -0.09% | 59 | 19 | Town |
| Arrowsic | 10 | 508 | 480 | 0.79% | 66 | 8 | Town |
Topsham is the largest city in Sagadahoc County, with a population of 9,976.
Arrowsic is the smallest city in Sagadahoc County, with a population of 508.
There are 10 cities in Sagadahoc County, Maine.