Addison
- County:
- Somerset County
- County Seat:
- No
- Area (mi²):
- 0.544
- State:
- Pennsylvania
Addison is a borough located in Somerset County, Pennsylvania. Addison has a 2026 population of 206. Addison is currently growing at a rate of 0.98% annually and its population has increased by 23.35% since the most recent census, which recorded a population of 167 in 2020.