| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sullivan | 1 | 14,609 | 14,781 | -0.1% | 200 | 73 | Town |
| Oneida | 2 | 9,942 | 10,314 | -0.67% | 451 | 22 | City |
| Lenox | 3 | 8,522 | 8,743 | -0.22% | 235 | 36 | Town |
| Cazenovia | 4 | 6,636 | 6,733 | -0.08% | 133 | 50 | Town |
| Hamilton | 5 | 6,352 | 6,383 | 0.06% | 154 | 41 | Town |
| Chittenango | 6 | 4,723 | 4,888 | -0.63% | 1,901 | 2 | Village |
| Eaton | 7 | 4,390 | 4,277 | -0.02% | 98 | 45 | Town |
| Canastota | 8 | 4,370 | 4,537 | -0.68% | 1,308 | 3 | Village |
| Hamilton | 9 | 4,069 | 4,107 | -0.22% | 1,632 | 2 | Village |
| Madison | 10 | 2,720 | 2,765 | -0.22% | 67 | 41 | Town |
| Cazenovia | 11 | 2,710 | 2,773 | -0.44% | 1,436 | 2 | Village |
| Brookfield | 12 | 2,235 | 2,244 | 0% | 29 | 78 | Town |
| Stockbridge | 13 | 1,964 | 1,984 | 0.15% | 62 | 32 | Town |
| Nelson | 14 | 1,877 | 1,893 | -0.11% | 44 | 43 | Town |
| Lincoln | 15 | 1,818 | 1,826 | 0.06% | 73 | 25 | Town |
| Morrisville | 16 | 1,804 | 1,759 | 0.5% | 1,762 | 1 | Village |
| Fenner | 17 | 1,606 | 1,631 | -0.25% | 52 | 31 | Town |
| Lebanon | 18 | 1,335 | 1,320 | 0.53% | 31 | 43 | Town |
| DeRuyter | 19 | 1,257 | 1,280 | 0% | 41 | 30 | Town |
| Smithfield | 20 | 1,099 | 1,117 | -0.09% | 45 | 24 | Town |
| Georgetown | 21 | 657 | 651 | 0.46% | 16 | 40 | Town |
| Oneida Castle | 22 | 575 | 593 | -0.69% | 1,136 | 1 | Village |
| Wampsville | 23 | 568 | 564 | -0.18% | 555 | 1 | Village |
| Munnsville | 24 | 431 | 450 | -0.92% | 492 | 1 | Village |
| Madison | 25 | 311 | 322 | -0.64% | 652 | 0 | Village |
Sullivan is the largest city in Madison County, with a population of 14,609.
Madison is the smallest city in Madison County, with a population of 311.
There are 25 cities in Madison County, New York.