Thornton, Colorado
Area codes 303, 720, 983 · Population: 118,772
Mountain (MT)
Colorado
Pop. 118,772
Area Codes Serving Thornton
About Thornton, Colorado
Thornton is a city in Colorado that is served by area codes 303, 720, 983. The city has a population of approximately 118,772 residents and is located in the Mountain Time Zone.