Smithfield
- County:
- Fayette County
- County Seat:
- No
- Area (mi²):
- 0.716
- State:
- Pennsylvania
Smithfield is a borough located in Fayette County, Pennsylvania. Smithfield has a 2026 population of 798. Smithfield is currently declining at a rate of -0.75% annually and its population has decreased by -3.86% since the most recent census, which recorded a population of 830 in 2020.