Carrolltown is a borough in Cambria County, Pennsylvania, United States. The population was 853 at the 2010 census, down from 1,049 at the 2000 census. It is part of the Johnstown, Pennsylvania Metropolitan Statistical Area.
Carrolltown is located in northern Cambria County at 40°36′N 78°43′W (40.603, -78.709), about 20 miles west of Altoona. U.S. Route 219 passes through the borough, leading northwest 6 miles (10 km) to Northern Cambria and south 8 miles (13 km) to Ebensburg, the county seat.
According to the United States Census Bureau, Carrolltown has a total area of 0.69 square miles (1.8 km2), all of it land.
As of the census of 2000, there were 1,049 people, 407 households, and 295 families living in the borough. The population density was 1,583.8 people per square mile (613.7/km2). There were 440 housing units at an average density of 664.3 per square mile (257.4/km2). The racial makeup of the borough was 99.62% White, 0.19% African American, and 0.19% from two or more races.
There were 407 households, out of which 29.2% had children under the age of 18 living with them, 59.0% were married couples living together, 10.8% had a female householder with no husband present, and 27.5% were non-families.