Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)
City | Rank | 2024 Pop. | 2020 Pop. | Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Syracuse | 1 | 145,171 | 146,726 | -0.27% | 5,793 | 25.1 | City |
| Clay | 2 | 59,355 | 60,437 | -0.39% | 1,235 | 48.1 | Town |
| Manlius | 3 | 32,875 | 33,662 | -0.48% | 669 | 49.1 | Town |
| Salina | 4 | 32,300 | 33,212 | -0.56% | 2,367 | 13.6 | Town |
| Cicero | 5 | 30,774 | 31,397 | -0.39% | 636 | 48.4 | Town |
| Camillus | 6 | 25,145 | 25,364 | -0.07% | 732 | 34.4 | Town |
| De Witt | 7 | 25,123 | 26,101 | -0.75% | 746 | 33.7 | Town |
| Lysander | 8 | 22,951 | 23,068 | -0.11% | 372 | 61.7 | Town |
| Onondaga | 9 | 22,309 | 22,816 | -0.26% | 387 | 57.6 | Town |
| Geddes | 10 | 16,628 | 17,002 | -0.4% | 1,813 | 9.2 | Town |
| Van Buren | 11 | 14,094 | 14,331 | -0.34% | 397 | 35.5 | Town |
| Baldwinsville | 12 | 7,583 | 7,806 | -0.73% | 2,377 | 3.2 | Village |
| Skaneateles | 13 | 7,041 | 7,113 | -0.24% | 165 | 42.6 | Town |
| Pompey | 14 | 7,001 | 7,069 | -0.26% | 105 | 66.4 | Town |
| North Syracuse | 15 | 6,773 | 6,731 | 0.15% | 3,409 | 2.0 | Village |
| Solvay | 16 | 6,434 | 6,632 | -0.77% | 3,981 | 1.6 | Village |
| Marcellus | 17 | 5,936 | 6,060 | -0.45% | 183 | 32.5 | Town |
| Elbridge | 18 | 5,377 | 5,469 | -0.32% | 143 | 37.6 | Town |
| LaFayette | 19 | 4,836 | 4,903 | -0.27% | 123 | 39.3 | Town |
| Manlius | 20 | 4,559 | 4,693 | -0.74% | 2,504 | 1.8 | Village |
| Fayetteville | 21 | 4,139 | 4,261 | -0.74% | 2,386 | 1.7 | Village |
| Minoa | 22 | 3,622 | 3,685 | -0.44% | 2,742 | 1.3 | Village |
| East Syracuse | 23 | 2,979 | 3,071 | -0.77% | 1,910 | 1.6 | Village |
| Tully | 24 | 2,621 | 2,670 | -0.19% | 101 | 25.9 | Town |
| Skaneateles | 25 | 2,511 | 2,545 | -0.36% | 1,765 | 1.4 | Village |
| Otisco | 26 | 2,367 | 2,369 | 0.17% | 80 | 29.5 | Town |
| Liverpool | 27 | 2,234 | 2,297 | -0.71% | 2,975 | 0.8 | Village |
| Fabius | 28 | 1,966 | 2,003 | -0.3% | 42 | 46.5 | Town |
| Marcellus | 29 | 1,742 | 1,792 | -0.74% | 2,726 | 0.6 | Village |
| Spafford | 30 | 1,603 | 1,587 | 0.75% | 49 | 32.6 | Town |
| Camillus | 31 | 1,287 | 1,223 | 1.26% | 3,170 | 0.4 | Village |
| Jordan | 32 | 1,195 | 1,225 | -0.66% | 1,027 | 1.2 | Village |
| Elbridge | 33 | 944 | 972 | -0.74% | 950 | 1.0 | Village |
| Tully | 34 | 884 | 911 | -0.79% | 1,209 | 0.7 | Village |
| Fabius | 35 | 323 | 333 | -0.92% | 758 | 0.4 | Village |
Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.
Syracuse is the largest city in Onondaga County.
Fabius is the smallest city in Onondaga County.
There are 35 cities in Onondaga County, New York.