
Cumberland County
- State:
- Pennsylvania
- County Seat:
- Carlisle
Cumberland County's estimated 2025 population is 275,150 with a growth rate of 0.81% in the past year according to the most recent United States census data. Cumberland County is the 15th largest county in Pennsylvania. The 2010 population was 235,903 and has seen a growth of 16.64% since that time.