Collinsville is a town in Grayson County, Texas, in the United States. The population was 1,624 at the 2010 census, up from 1,235 at the 2000 census. It is part of the Sherman–Denison Metropolitan Statistical Area.
Collinsville is located on U.S. Route 377 south of Whitesboro.
In 1904, Collinsville Academy was built. The school had two stories, six rooms, and could accommodate about 400 students. The school was rebuilt in 1941 with Roosevelt's New Deal to help the citizens of Collinsville retain jobs during the Depression, according to the older citizens of the community. A 20-room school was built to replace it, and continues to be used as an elementary school. A high school and junior high were built in 1995.
Collinsville is located in southwestern Grayson County at 33°33′39″N 96°54′40″W (33.560731, -96.911027). US 377 passes through the west side of the town, leading north 7 miles (11 km) to Whitesboro and south 12 miles (19 km) to Pilot Point.