The company said in a news release the 24-hour establishment is its first on a domestic U.S. military base, although it already operates an outlet at the Kandahar Airfield in Afghanistan for British, Canadian and U.S. NATO troops.
It also has franchises at seven Canadian military bases.
The outlet at Fort Knox, the U.S. military's armor center and also the U.S. storage site for the country's gold bullion, will serve some 30,000 military members, their families and civilians, the release said.
The company is named for its founder, former NHL hockey player Tim Horton, who died in 1974. It is based west of Toronto in Oakville, Ontario, with its U.S. headquarters in Dublin, Ohio.
The company has some 500 outlets in the United States and 3,000 elsewhere in the world.