Lewistown
- County:
- Mifflin County
- County Seat:
- Yes
- Area (mi²):
- 2.03
- State:
- Pennsylvania
Lewistown is a borough located in Mifflin County, Pennsylvania. Lewistown has a 2026 population of 8,394. It is also the county seat of Mifflin County. Lewistown is currently declining at a rate of -0.32% annually and its population has decreased by -1.99% since the most recent census, which recorded a population of 8,564 in 2020.