51 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Wellsville | 1 | 6,913 | 7,047 | -0.2% | 189 | 37 | Town |
| Alfred | 2 | 6,545 | 6,131 | -0.11% | 208 | 31 | Town |
| Alfred | 3 | 5,578 | 5,042 | 1.96% | 4,687 | 1 | Village |
| Wellsville | 4 | 4,530 | 4,632 | -0.46% | 1,869 | 2 | Village |
| Cuba | 5 | 3,070 | 3,124 | -0.52% | 87 | 35 | Town |
| Caneadea | 6 | 2,250 | 2,276 | -0.09% | 63 | 36 | Town |
| Amity | 7 | 2,129 | 2,173 | -0.09% | 62 | 34 | Town |
| Hume | 8 | 2,037 | 2,075 | -0.29% | 54 | 38 | Town |
| Bolivar | 9 | 1,971 | 2,027 | -0.5% | 55 | 36 | Town |
| Friendship | 10 | 1,932 | 1,941 | 0.1% | 53 | 36 | Town |
| Houghton | 11 | 1,790 | 1,683 | 0.34% | 658 | 3 | CDP |
| Belfast | 12 | 1,632 | 1,638 | 0.43% | 45 | 36 | Town |
| Genesee | 13 | 1,595 | 1,634 | -0.37% | 44 | 36 | Town |
| Scio | 14 | 1,595 | 1,613 | -0.25% | 45 | 35 | Town |
| Andover | 15 | 1,572 | 1,616 | -0.44% | 40 | 39 | Town |
| Almond | 16 | 1,499 | 1,507 | 0.33% | 33 | 46 | Town |
| Cuba | 17 | 1,495 | 1,540 | -0.6% | 1,229 | 1 | Village |
| Angelica | 18 | 1,277 | 1,273 | 0.39% | 35 | 36 | Town |
| Willing | 19 | 1,247 | 1,281 | -0.32% | 34 | 36 | Town |
| Independence | 20 | 1,086 | 1,083 | 0.37% | 31 | 34 | Town |
| Rushford | 21 | 1,071 | 1,073 | 0.19% | 30 | 35 | Town |
| Wirt | 22 | 1,022 | 1,047 | -0.29% | 28 | 36 | Town |
| Burns | 23 | 1,017 | 1,033 | -0.1% | 37 | 27 | Town |
| Bolivar | 24 | 995 | 1,024 | -0.6% | 1,248 | 1 | Village |
| Centerville | 25 | 972 | 926 | 1.89% | 27 | 35 | Town |
| Andover | 26 | 885 | 912 | -0.67% | 884 | 1 | Village |
| Belmont | 27 | 829 | 853 | -0.6% | 832 | 1 | Village |
| New Hudson | 28 | 795 | 795 | -0.13% | 22 | 36 | Town |
| North Hornell | 29 | 761 | 779 | -0.52% | 1,550 | 0 | Village |
| Alma | 30 | 758 | 776 | -0.39% | 21 | 36 | Town |
| Friendship | 31 | 737 | 854 | -4.16% | 255 | 3 | CDP |
| Angelica | 32 | 704 | 718 | -0.42% | 327 | 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 | 521 | 516 | 0% | 16 | 32 | Town |
| Rushford | 38 | 513 | 403 | 1.99% | 874 | 1 | CDP |
| Allen | 39 | 511 | 487 | 2.61% | 14 | 36 | Town |
| Grove | 40 | 501 | 492 | 0.8% | 15 | 33 | Town |
| Canaseraga | 41 | 451 | 465 | -0.66% | 425 | 1 | Village |
| Groveland Station | 42 | 446 | 373 | 2.53% | 761 | 1 | CDP |
| Richburg | 43 | 403 | 416 | -0.74% | 448 | 1 | Village |
| Almond | 44 | 394 | 404 | -0.51% | 699 | 1 | Village |
| Ward | 45 | 330 | 329 | 0% | 11 | 29 | Town |
| West Almond | 46 | 277 | 277 | 0.36% | 8 | 36 | Town |
| Birdsall | 47 | 188 | 189 | 0% | 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 6,913.
Kysorville is the smallest city in Allegany County, with a population of 46.
There are 51 cities in Allegany County, New York.