
Montgomery County
- State:
- Pennsylvania
- County Seat:
- Norristown
Montgomery County's estimated 2025 population is 876,138 with a growth rate of 0.42% in the past year according to the most recent United States census data. Montgomery County is the 3rd largest county in Pennsylvania. The 2010 population was 800,881 and has seen a growth of 9.4% since that time.