51 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Wellsville | 1 | 6,870 | 7,046 | -0.56% | 187 | 37 | Town |
| Alfred | 2 | 5,955 | 6,129 | 0.68% | 189 | 31 | Town |
| Alfred | 3 | 4,622 | 5,039 | -1.76% | 3,884 | 1 | Village |
| Wellsville | 4 | 4,521 | 4,633 | -0.48% | 1,865 | 2 | Village |
| Cuba | 5 | 3,110 | 3,120 | 0.1% | 89 | 35 | Town |
| Caneadea | 6 | 2,229 | 2,270 | -0.54% | 63 | 36 | Town |
| Amity | 7 | 2,117 | 2,169 | -0.33% | 61 | 34 | Town |
| Hume | 8 | 2,030 | 2,073 | -0.39% | 53 | 38 | Town |
| Bolivar | 9 | 1,966 | 2,027 | -0.66% | 55 | 36 | Town |
| Friendship | 10 | 1,916 | 1,938 | -0.21% | 53 | 36 | Town |
| Houghton | 11 | 1,790 | 1,683 | 0.34% | 658 | 3 | CDP |
| Belfast | 12 | 1,612 | 1,637 | -0.19% | 44 | 36 | Town |
| Scio | 13 | 1,603 | 1,614 | -0.06% | 45 | 35 | Town |
| Genesee | 14 | 1,589 | 1,633 | -0.5% | 44 | 36 | Town |
| Andover | 15 | 1,571 | 1,616 | -0.51% | 40 | 39 | Town |
| Cuba | 16 | 1,513 | 1,537 | -0.33% | 1,244 | 1 | Village |
| Almond | 17 | 1,474 | 1,510 | -0.54% | 32 | 46 | Town |
| Angelica | 18 | 1,268 | 1,272 | 0.08% | 35 | 36 | Town |
| Willing | 19 | 1,239 | 1,282 | -0.72% | 34 | 36 | Town |
| Rushford | 20 | 1,068 | 1,073 | 0% | 30 | 35 | Town |
| Independence | 21 | 1,066 | 1,083 | -0.37% | 31 | 34 | Town |
| Wirt | 22 | 1,020 | 1,046 | -0.49% | 28 | 36 | Town |
| Burns | 23 | 1,015 | 1,033 | -0.29% | 37 | 27 | Town |
| Bolivar | 24 | 996 | 1,023 | -0.5% | 1,250 | 1 | Village |
| Centerville | 25 | 942 | 925 | 0.32% | 27 | 35 | Town |
| Andover | 26 | 883 | 912 | -0.67% | 882 | 1 | Village |
| Belmont | 27 | 826 | 853 | -0.6% | 829 | 1 | Village |
| New Hudson | 28 | 803 | 790 | 0.63% | 22 | 36 | Town |
| North Hornell | 29 | 784 | 778 | 0.13% | 1,597 | 0 | Village |
| Alma | 30 | 765 | 777 | -0.26% | 21 | 36 | Town |
| Friendship | 31 | 737 | 854 | -4.16% | 255 | 3 | CDP |
| Angelica | 32 | 702 | 719 | -0.43% | 326 | 2 | Village |
| Fillmore | 33 | 664 | 538 | 0.61% | 700 | 1 | CDP |
| Belfast | 34 | 608 | 752 | -2.56% | 393 | 2 | CDP |
| Scio | 35 | 584 | 688 | -0.34% | 441 | 1 | CDP |
| Stannards | 36 | 571 | 632 | -2.56% | 204 | 3 | CDP |
| Granger | 37 | 528 | 517 | 0.57% | 17 | 32 | Town |
| Rushford | 38 | 513 | 403 | 1.99% | 874 | 1 | CDP |
| Grove | 39 | 500 | 491 | 0.6% | 15 | 33 | Town |
| Allen | 40 | 496 | 489 | 0.81% | 14 | 36 | Town |
| Canaseraga | 41 | 453 | 465 | -0.44% | 427 | 1 | Village |
| Groveland Station | 42 | 446 | 373 | 2.53% | 761 | 1 | CDP |
| Richburg | 43 | 406 | 416 | -0.49% | 451 | 1 | Village |
| Almond | 44 | 394 | 404 | -0.51% | 699 | 1 | Village |
| Ward | 45 | 330 | 328 | 0% | 11 | 29 | Town |
| West Almond | 46 | 276 | 277 | 0% | 8 | 36 | Town |
| Birdsall | 47 | 189 | 188 | 0.53% | 5 | 36 | Town |
| Woodsville | 48 | 84 | 65 | 7.69% | 265 | 0 | CDP |
| Cumminsville | 49 | 62 | 68 | -11.43% | 473 | 0 | CDP |
| Byersville | 50 | 58 | 34 | 7.41% | 114 | 1 | CDP |
| Kysorville | 51 | 46 | 47 | -8% | 56 | 1 | CDP |
Wellsville is the largest city in Allegany County, with a population of 6,870.
Kysorville is the smallest city in Allegany County, with a population of 46.
There are 51 cities in Allegany County, New York.