If you’re in the central Colorado area and need to get ahold of someone, chances are you’ll be using area code 720. The main locations covered by this area code include Denver, Thornton, Arvada—and they’re all pretty close together!
720 has been in service since June 1st, 1998. It’s part of an overlay complex that includes 303/720/983.
Colorado Counties within Area Code 720:
Denver, Arapahoe, Jefferson, Adams, Boulder, Douglas, Broomfield, Weld, Elbert, Clear Creek, Gilpin, Park.
Colorado Major Cities within Area Code 720:
Denver, Aurora, Lakewood, Thornton, Arvada, Westminster, Centennial, Boulder, Highlands Ranch, Longmont, Broomfield, Castle Rock, Commerce City, Parker, Littleton, Northglenn, Brighton, Ken Caryl, Dakota Ridge, Englewood, Wheat Ridge, Lafayette, Columbine, Golden, Louisville, Sherrelwood, Erie, Welby, Greenwood Village, Superior, Federal Heights, Berkley, Cherry Creek, The Pinery, Castle Pines North, Lone Tree, Firestone, Gunbarrel, Roxborough Park, Evergreen, Stonegate, Frederick, Derby, Fairmount, Fort Lupton, Applewood, Twin Lakes, Cherry Hills Village, Sheridan, Dove Valley.
Area Code 720 Time Zone?
Mountain time zone is also known as America/Denver.
Go here to see the complete list of United States Area Codes.