19 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Northampton | 1 | 31,824 | 29,279 | 1.63% | 929 | 34 | City |
| Northampton | 2 | 31,246 | 29,279 | -0.22% | 912 | 34 | City |
| South Hadley | 3 | 17,958 | 16,306 | -0.4% | 1,014 | 18 | Town |
| Belchertown | 4 | 15,337 | 15,339 | -0.23% | 292 | 53 | Town |
| Ware | 5 | 10,172 | 10,037 | 0.3% | 296 | 34 | Town |
| Southampton | 6 | 6,139 | 6,221 | -0.68% | 218 | 28 | Town |
| Granby | 7 | 6,045 | 6,099 | -0.31% | 217 | 28 | Town |
| Hadley | 8 | 5,265 | 5,317 | -0.36% | 228 | 23 | Town |
| Hatfield | 9 | 3,308 | 3,338 | -0.39% | 208 | 16 | Town |
| Williamsburg | 10 | 2,470 | 2,500 | -0.2% | 97 | 26 | Town |
| Huntington | 11 | 2,062 | 2,095 | -0.43% | 78 | 26 | Town |
| Westhampton | 12 | 1,627 | 1,615 | -0.12% | 60 | 27 | Town |
| Pelham | 13 | 1,414 | 1,281 | 5.29% | 56 | 25 | Town |
| Worthington | 14 | 1,177 | 1,192 | -0.34% | 37 | 32 | Town |
| Chesterfield | 15 | 1,169 | 1,186 | -0.43% | 38 | 31 | Town |
| Goshen | 16 | 936 | 960 | -0.64% | 54 | 17 | Town |
| Cummington | 17 | 815 | 827 | -0.49% | 36 | 23 | Town |
| Plainfield | 18 | 660 | 630 | 1.69% | 31 | 21 | Town |
| Middlefield | 19 | 400 | 389 | 0.76% | 17 | 24 | Town |
Northampton is the largest city in Hampshire County, with a population of 31,824.
Middlefield is the smallest city in Hampshire County, with a population of 400.
There are 19 cities in Hampshire County, Massachusetts.