Grassflat is a census-designated place located in Cooper Township, Clearfield County, in the state of Pennsylvania. As of the 2020 census, the population was 479.

Pennsylvania Route 53 passes just west of the community, leading 3 miles (5 km) southwest to Interstate 80, Exit 133 at Kylertown and 12 miles (19 km) east to Snow Shoe.

Demographics

Historical population

Census	Pop.	Note	%±
2010	511		—
2020	479		−6.3%
U.S. Decennial Census