| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Fernandina Beach | 1 | 14,024 | 13,101 | 1.12% | 1,184 | 12 | City |
| Hilliard | 2 | 3,191 | 2,956 | 0.95% | 579 | 6 | Town |
| Callahan | 3 | 1,892 | 1,551 | 3.39% | 1,047 | 2 | Town |
Fernandina Beach is the largest city in Nassau County, with a population of 14,024.
Callahan is the smallest city in Nassau County, with a population of 1,892.
There are 3 cities in Nassau County, Florida.