20 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Batavia | 1 | 15,019 | 15,174 | -0.17% | 2,891 | 5 | City |
| Le Roy | 2 | 7,633 | 7,643 | 0.45% | 181 | 42 | Town |
| Batavia | 3 | 6,628 | 6,684 | -0.17% | 138 | 48 | Town |
| Le Roy | 4 | 4,221 | 4,365 | -0.57% | 1,569 | 3 | Village |
| Pembroke | 5 | 4,194 | 4,261 | -0.02% | 101 | 42 | Town |
| Oakfield | 6 | 3,080 | 3,145 | -0.1% | 132 | 23 | Town |
| Bergen | 7 | 3,075 | 3,121 | 0.13% | 112 | 28 | Town |
| Darien | 8 | 2,964 | 3,014 | -0.24% | 63 | 47 | Town |
| Alexander | 9 | 2,451 | 2,480 | 0.2% | 69 | 35 | Town |
| Stafford | 10 | 2,358 | 2,424 | -0.3% | 76 | 31 | Town |
| Byron | 11 | 2,250 | 2,298 | -0.18% | 70 | 32 | Town |
| Pavilion | 12 | 2,217 | 2,289 | -0.4% | 62 | 36 | Town |
| Elba | 13 | 2,116 | 2,154 | -0.19% | 59 | 36 | Town |
| Oakfield | 14 | 1,772 | 1,826 | -0.51% | 2,681 | 1 | Village |
| Bethany | 15 | 1,742 | 1,780 | -0.23% | 48 | 36 | Town |
| Alabama | 16 | 1,555 | 1,605 | -0.45% | 37 | 42 | Town |
| Bergen | 17 | 1,195 | 1,239 | -0.58% | 1,621 | 1 | Village |
| Corfu | 18 | 682 | 703 | -0.44% | 685 | 1 | Village |
| Elba | 19 | 583 | 603 | -0.51% | 573 | 1 | Village |
| Alexander | 20 | 484 | 505 | -0.62% | 1,108 | 0 | Village |
Batavia is the largest city in Genesee County, with a population of 15,019.
Alexander is the smallest city in Genesee County, with a population of 484.
There are 20 cities in Genesee County, New York.