| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Boston | 1 | 671,635 | 669,665 | -0.2% | 13,894 | 48 | City |
| Revere | 2 | 59,907 | 61,909 | -0.39% | 10,503 | 6 | City |
| Chelsea | 3 | 40,086 | 40,543 | -0.11% | 18,065 | 2 | City |
| Winthrop Town | 4 | 18,619 | 19,255 | -0.15% | 9,352 | 2 | City |
Boston is the largest city in Suffolk County, with a population of 671,635.
Winthrop Town is the smallest city in Suffolk County, with a population of 18,619.
There are 4 cities in Suffolk County, Massachusetts.