720 Area Code: Cities, Time Zone and Zip Codes
What area code is 720? The area code 720 is located in Colorado and it serves Denver, Aurora, Lakewood, Thornton, Arvada, Westminster, Centennial, Boulder, Highlands Ranch, Longmont, and some other surrounding cities. The area code 720 was created from area code 303 on March 3, 1998, and was first put to use on June 1,