The area code 605 is located in Rapid City, South Dakota.
Area code 605 serves Rapid City, South Dakota, a hub on the eastern edge of the Black Hills. It links Rapid City with communities across the state, from the prairie to the pine-covered hills. The code was established in 1947 as part of the original North American Numbering Plan, making it one of the longest-running area codes in the U.S. It spans two time zones across the state, with Rapid City in the Mountain Time zone.
"Area code 605 was assigned in 1947." — North American Numbering Plan Administrator (NANPA)
Major cities and landmarks covered by 605 include:
In Rapid City, 605 connects callers to outdoor landmarks and local life. The city is known as the “Gateway to the Black Hills” and the “City of Presidents” for its downtown statues of U.S. presidents. Iconic sites like Mount Rushmore sit about 25 miles southwest of town, while the rugged Badlands stretch to the east. Each August, nearby Sturgis hosts the famous motorcycle rally, drawing visitors and phone traffic from around the world.
For calling, use the U.S. format 1 + 605 + seven digits, or dial +1 605 from abroad. 605 phone numbers include both landline and mobile exchanges across urban and rural areas. Because the code covers a vast, low‑density state, it serves a wide mix of communities—small towns, tribal lands, and growing city centers—all tied together by one historic area code.