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 |
|---|---|---|---|---|---|---|---|
| Brookhaven | 1 | 487,160 | 484,578 | -0.24% | 1,876 | 259.6 | Town |
| Islip | 2 | 335,258 | 339,077 | -0.46% | 3,249 | 103.2 | Town |
| Babylon | 3 | 216,046 | 217,663 | -0.46% | 4,133 | 52.3 | Town |
| Huntington | 4 | 202,264 | 203,585 | -0.32% | 2,151 | 94.0 | Town |
| Smithtown | 5 | 114,992 | 115,897 | -0.4% | 2,139 | 53.8 | Town |
| Southampton | 6 | 69,859 | 68,842 | 0.23% | 503 | 138.8 | Town |
| Riverhead | 7 | 35,561 | 35,815 | -0.45% | 528 | 67.4 | Town |
| East Hampton | 8 | 28,885 | 28,363 | 0.42% | 388 | 74.4 | Town |
| Lindenhurst | 9 | 26,932 | 27,091 | -0.15% | 7,188 | 3.7 | Village |
| Southold | 10 | 23,769 | 23,735 | -0.36% | 442 | 53.8 | Town |
| Patchogue | 11 | 12,325 | 12,373 | -0.1% | 5,454 | 2.3 | Village |
| Babylon | 12 | 12,085 | 12,168 | -0.17% | 5,012 | 2.4 | Village |
| Lake Grove | 13 | 11,015 | 11,038 | -0.05% | 3,739 | 2.9 | Village |
| Amityville | 14 | 9,615 | 9,463 | 0.4% | 4,677 | 2.1 | Village |
| Port Jefferson | 15 | 8,184 | 7,963 | 0.68% | 2,672 | 3.1 | Village |
| Northport | 16 | 7,253 | 7,332 | -0.27% | 3,149 | 2.3 | Village |
| Southampton | 17 | 4,656 | 4,538 | 0.63% | 714 | 6.5 | Village |
| Greenport | 18 | 4,337 | 4,461 | -0.94% | 233 | 18.6 | Town |
| Islandia | 19 | 3,647 | 3,565 | 0.55% | 1,647 | 2.2 | Village |
| Lloyd Harbor | 20 | 3,528 | 3,563 | -0.25% | 378 | 9.3 | Village |
| Shelter Island | 21 | 3,305 | 3,253 | 0.4% | 271 | 12.2 | Town |
| Brightwaters | 22 | 3,164 | 3,182 | -0.16% | 3,275 | 1.0 | Village |
| Sag Harbor | 23 | 2,796 | 2,752 | 0.4% | 1,565 | 1.8 | Village |
| Greenport | 24 | 2,549 | 2,596 | -0.47% | 2,683 | 0.9 | Village |
| Westhampton Beach | 25 | 2,198 | 2,174 | 0.27% | 748 | 2.9 | Village |
| Bellport | 26 | 2,195 | 2,195 | 0% | 1,514 | 1.4 | Village |
| Village Branch | 27 | 1,743 | 1,765 | -0.34% | 1,835 | 0.9 | Village |
| Quogue | 28 | 1,709 | 1,659 | 0.71% | 410 | 4.2 | Village |
| Nissequogue | 29 | 1,607 | 1,603 | 0.06% | 422 | 3.8 | Village |
| East Hampton | 30 | 1,557 | 1,511 | 0.71% | 326 | 4.8 | Village |
| Head Harbor | 31 | 1,462 | 1,480 | -0.34% | 521 | 2.8 | Village |
| Huntington Bay | 32 | 1,426 | 1,425 | 0% | 1,429 | 1.0 | Village |
| North Haven | 33 | 1,183 | 1,149 | 0.68% | 446 | 2.7 | Village |
| Poquott | 34 | 922 | 928 | -0.22% | 2,105 | 0.4 | Village |
| Old Field | 35 | 896 | 908 | -0.33% | 433 | 2.1 | Village |
| Belle Terre | 36 | 785 | 784 | 0% | 887 | 0.9 | Village |
| Sagaponack | 37 | 737 | 731 | 0.14% | 167 | 4.4 | Village |
| Asharoken | 38 | 605 | 593 | 0.5% | 425 | 1.4 | Village |
| Shoreham | 39 | 522 | 521 | 0% | 1,150 | 0.5 | Village |
| Ocean Beach | 40 | 168 | 166 | 0% | 1,191 | 0.1 | Village |
| West Hampton Dunes | 41 | 118 | 114 | 0.85% | 377 | 0.3 | Village |
| Saltaire | 42 | 111 | 110 | 0% | 476 | 0.2 | Village |
| Dering Harbor | 43 | 35 | 34 | 0% | 142 | 0.2 | 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.
Brookhaven is the largest city in Suffolk County.
Dering Harbor is the smallest city in Suffolk County.
There are 43 cities in Suffolk County, New York.