Northumberland County Flag

Northumberland County

State:
Pennsylvania
County Seat:
Sunbury

Northumberland County's 2026 population is estimated at 89,819, reflecting a -0.12% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Northumberland County is the 32nd largest county in Pennsylvania. The 2010 population was 94,287 and has grown -4.74% since 2010.

89,819
Total Population
196
Population Density (mi²)
32
Population Rank (State)
-104 -0.12%
Annual Population Growth

Northumberland County Population

Demographics

Economics and Income Statistics