
Nassau County
- State:
- Florida
- County Seat:
- Fernandina
Nassau County's estimated 2025 population is 108,851 with a growth rate of 3.49% in the past year according to the most recent United States census data. Nassau County is the 37th largest county in Florida. The 2010 population was 73,526 and has seen a growth of 48.04% since that time.