16 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Barnstable Town | 1 | 50,070 | 48,872 | 0.48% | 835 | 60 | City |
| Barnstable Town | 2 | 49,704 | 48,872 | -0.25% | 829 | 60 | City |
| Falmouth | 3 | 33,247 | 32,541 | 0.06% | 755 | 44 | Town |
| Yarmouth | 4 | 25,179 | 24,990 | -0.12% | 1,042 | 24 | Town |
| Bourne | 5 | 20,544 | 19,604 | 0.18% | 505 | 41 | Town |
| Sandwich | 6 | 20,459 | 20,254 | -0.23% | 477 | 43 | Town |
| Mashpee | 7 | 15,479 | 15,068 | -0.02% | 662 | 23 | Town |
| Dennis | 8 | 14,762 | 14,676 | -0.67% | 717 | 21 | Town |
| Harwich | 9 | 13,589 | 13,430 | -0.23% | 651 | 21 | Town |
| Brewster | 10 | 10,466 | 10,318 | 0.18% | 456 | 23 | Town |
| Chatham | 11 | 6,713 | 6,593 | 0.03% | 415 | 16 | Town |
| Orleans | 12 | 6,552 | 6,306 | 1.03% | 463 | 14 | Town |
| Eastham | 13 | 5,823 | 5,746 | -0.02% | 417 | 14 | Town |
| Provincetown | 14 | 3,731 | 3,658 | 0.05% | 386 | 10 | Town |
| Wellfleet | 15 | 3,648 | 3,565 | 0.08% | 184 | 20 | Town |
| Truro | 16 | 2,485 | 2,439 | 0.04% | 119 | 21 | Town |
Barnstable Town is the largest city in Barnstable County, with a population of 50,070.
Truro is the smallest city in Barnstable County, with a population of 2,485.
There are 16 cities in Barnstable County, Massachusetts.