
Northumberland County
- State:
- Virginia
- County Seat:
- Heathsville
Northumberland County's estimated 2025 population is 12,617 with a growth rate of 0.9% in the past year according to the most recent United States census data. Northumberland County is the 107th largest county in Virginia. The 2010 population was 12,356 and has seen a growth of 2.11% since that time.