Eau Claire
- County:
- Butler County
- County Seat:
- No
- Area (mi²):
- 1.275
- State:
- Pennsylvania
Eau Claire is a borough located in Butler County, Pennsylvania. Eau Claire has a 2026 population of 295. Eau Claire is currently declining at a rate of -1.01% annually and its population has decreased by -3.59% since the most recent census, which recorded a population of 306 in 2020.
The median household income in Eau Claire is $61,719 with a poverty rate of 13.6%. The median age in Eau Claire is 39.6 years: 37.9 years for males, and 43.5 years for females. For every 100 females there are 132.5 males.