Sioux Falls, SD Area Code

Area code serving Sioux Falls

Sioux Falls sits in South Dakota, part of the Midwest region and the Central Time zone. Its area code is 605, which covers the entire state of South Dakota. 605 has no overlay today, so every Sioux Falls landline and mobile number with a local code starts with 605.

605 has served the area since 1947, as one of the original 1947 North American area codes. If the region runs low on numbers, regulators will most likely add an overlay code on top rather than split the area, which would make 10-digit dialing mandatory.

Code	Area served	In service
605	The entire state of South Dakota	January 1, 1947

Nearby cities sharing this area code

• Rapid City
• Aberdeen
• Brookings
• Watertown
• Mitchell
• Yankton
• Pierre
• Huron
• Brandon
• Spearfish
• Vermillion
• Box Elder

Getting a Sioux Falls phone number

Any new landline, mobile or VoIP number from a local carrier in Sioux Falls gets the 605 area code. Numbers come from the blocks each carrier holds in the area; a number ported in from elsewhere keeps its original area code, so you may also see out-of-state codes locally.

Dialing in Sioux Falls

Sioux Falls is covered by the single area code 605 with no overlay, so some local calls may still connect with seven digits. Dialing all 10 digits (area code + seven-digit number) always works and is the safest habit. From outside the US, dial +1, then the area code and number. See 10-digit dialing and overlay area codes for the background. For every code in South Dakota, visit the South Dakota area codes page.