26 cities
| City | Rank | County | 2025 Pop. ↓ |
|---|---|---|---|
| Milford | 1 | Sussex County | 14,608 |
| Seaford | 2 | Sussex County | 9,231 |
| Georgetown | 3 | Sussex County | 8,332 |
| Millsboro | 4 | Sussex County | 8,099 |
| Laurel | 5 | Sussex County | 4,529 |
| Milton | 6 | Sussex County | 3,897 |
| Lewes | 7 | Sussex County | 3,794 |
| Selbyville | 8 | Sussex County | 3,374 |
| Long Neck | 9 | Sussex County | 3,234 |
| Ocean View | 10 | Sussex County | 3,120 |
| Bridgeville | 11 | Sussex County | 2,999 |
| Delmar | 12 | Sussex County | 2,334 |
| Millville | 13 | Sussex County | 2,177 |
| Lincoln | 14 | Sussex County | 1,799 |
| Blades | 15 | Sussex County | 1,372 |
| Rehoboth Beach | 16 | Sussex County | 1,292 |
| Greenwood | 17 | Sussex County | 1,153 |
| Bethany Beach | 18 | Sussex County | 1,123 |
| Dagsboro | 19 | Sussex County | 1,019 |
| Frankford | 20 | Sussex County | 929 |
| Ellendale | 21 | Sussex County | 573 |
| South Bethany | 22 | Sussex County | 534 |
| Dewey Beach | 23 | Sussex County | 417 |
| Fenwick Island | 24 | Sussex County | 398 |
| Bethel | 25 | Sussex County | 273 |
| Henlopen Acres | 26 | Sussex County | 161 |
Sussex County are the counties that are generally considered part of South Delaware.