| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Dover | 1 | 40,815 | 39,417 | 0.55% | 1,714 | 24 | City |
| Smyrna | 2 | 13,433 | 12,961 | 0.7% | 2,096 | 6 | Town |
| Clayton | 3 | 4,657 | 3,991 | 2.87% | 2,391 | 2 | Town |
| Camden | 4 | 4,293 | 3,721 | 2.8% | 1,146 | 4 | Town |
| Harrington | 5 | 4,013 | 3,787 | 0.98% | 1,305 | 3 | City |
| Cheswold | 6 | 2,804 | 1,938 | 5.69% | 1,438 | 2 | Town |
| Wyoming | 7 | 1,906 | 1,706 | 2.2% | 1,820 | 1 | Town |
| Felton | 8 | 1,400 | 1,315 | 1.01% | 1,777 | 1 | Town |
| Frederica | 9 | 1,168 | 1,092 | 1.13% | 671 | 2 | Town |
| Houston | 10 | 408 | 387 | 0.74% | 1,065 | 0 | Town |
| Bowers | 11 | 293 | 275 | 1.03% | 942 | 0 | Town |
| Magnolia | 12 | 293 | 280 | 0.69% | 1,495 | 0 | Town |
| Slaughter Beach | 13 | 262 | 222 | 2.75% | 185 | 1 | Town |
| Kenton | 14 | 233 | 218 | 0.87% | 1,324 | 0 | Town |
| Woodside | 15 | 203 | 186 | 1.5% | 1,208 | 0 | Town |
| Little Creek | 16 | 201 | 189 | 1.01% | 2,030 | 0 | Town |
| Leipsic | 17 | 199 | 187 | 1.02% | 670 | 0 | Town |
| Viola | 18 | 146 | 139 | 0.69% | 825 | 0 | Town |
| Farmington | 19 | 103 | 89 | 1.98% | 1,411 | 0 | Town |
| Hartly | 20 | 81 | 71 | 2.53% | 1,421 | 0 | Town |
Dover is the largest city in Kent County, with a population of 40,815.
Hartly is the smallest city in Kent County, with a population of 81.
There are 20 cities in Kent County, Delaware.