Beaver is a borough in, and the county seat of, Beaver County, Pennsylvania, United States. It is located near the confluence of the Beaver and Ohio Rivers, approximately 30 miles (48 km) northwest of Pittsburgh. As of the 2020 census, the population was 4,438.

Beaver County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 168,215. Its county seat is Beaver, and its largest city is Aliquippa. The county is part of the Greater Pittsburgh region of the state.