About Area Code 605
- Region Code
- 605
- City
- Sioux Falls
- State
- South Dakota
- Population
- 886,667
- Largest City
- Sioux Falls
- Neighboring Codes
- Time Zone
- Central Time
South Dakota
(605) Area Code 605 — Sioux Falls, South Dakota
605 Area Code – Sioux Falls, South Dakota: Location, Time Zone & History
Build trust, look local, and grow your business with a phone number in area code 605. Instant activation, flexible forwarding, and clear pricing.
Map of Area Code 605
Available Phone Numbers
Choose from popular and easy-to-remember local numbers. Instant purchase and activation.
History & Cultural Notes
South Dakota has used a single telephone area code, 605, since the North American Numbering Plan was rolled out in 1947, and it has never been split or overlaid. That continuity is unusual: most states with 605's population have needed at least one additional code over the decades, but South Dakota's numbering needs have stayed within the original allocation.
One quirk of the state's geography adds a layer of interest to that single-code status. South Dakota spans two time zones, with Sioux Falls, Aberdeen, Brookings, Watertown, and Pierre in the Central zone while Rapid City and the Black Hills observe Mountain Time, yet all of it dials under 605. The only real change to the dialing experience came in 2021, when ten-digit local dialing became mandatory statewide ahead of the nationwide activation of 988 as the Suicide & Crisis Lifeline number.
- Financial services and banking centered in Sioux Falls
- Agriculture and agribusiness across the state
- Healthcare
- Tourism tied to the Black Hills and Mount Rushmore
- Manufacturing
Beyond Sioux Falls, the code also serves Rapid City, Aberdeen, Brookings, Mitchell, and Pierre, tying together a state whose economic base spans finance, farming, and tourism under one unbroken numbering plan.