8 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Boston | 1 | 691,168 | 675,522 | 1.3% | 14,298 | 48 | City |
| Boston | 2 | 672,426 | 675,522 | -0.08% | 13,910 | 48 | City |
| Revere | 3 | 64,174 | 61,911 | 2.78% | 11,251 | 6 | City |
| Revere | 4 | 60,097 | 61,911 | -0.5% | 10,536 | 6 | City |
| Chelsea | 5 | 41,683 | 40,549 | 1.76% | 18,785 | 2 | City |
| Chelsea | 6 | 40,093 | 40,549 | -0.19% | 18,068 | 2 | City |
| Winthrop Town | 7 | 19,051 | 19,257 | 0.83% | 9,569 | 2 | City |
| Winthrop Town | 8 | 18,480 | 19,257 | -0.69% | 9,282 | 2 | City |
Boston is the largest city in Suffolk County, with a population of 691,168.
Winthrop Town is the smallest city in Suffolk County, with a population of 18,480.
There are 8 cities in Suffolk County, Massachusetts.