The first St John's church was built in 1807 and destroyed by the Kentucky Mounted Riflemen in the war of 1812. The church was rebuilt in 1818 and the current church built in 1872. St. John's, Sandwich, is the mother church of eight other parishes, including the Cathedral Church of St. Paul in Detroit, Michigan. Seven of those eight parishes are still open and holding worship services on a regular basis.
In 1935, Sandwich was one of the four communities amalgamated to form the City of Windsor, Ontario.
Current projects of the parish include the food bank, the Mission to Seamen and the seniors' housing project. Rector is Rev Bill Bradley. Sunday services are 8:00am and 10:00am and there is a Wednesday service at 10:00am.