Interior South Dakota Area Code

One area code covers Interior: 605.

The code covering Interior

Area codes covering Interior, South Dakota, with what each one primarily serves.
Area code	Primarily serves	In service
605	Sioux Falls	1947

Scope the codes matched to Interior. Source geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot) and LocalCallingGuide NPA list (2026-07 NPA list). Updated 16 July 2026. Overlay relationships come from the numbering-plan authority; the place match is computed.

Which part of town has which code

Interior has a single code, so there is nothing to divide — every local line carries 605.

ZIP codes for the same city

Postal geography is organised separately from telephone geography, so Interior’s 1 ZIP code do not map onto the codes above. They are listed in full, with the county each falls in, on the postal side of the site.

Interior South Dakota ZIP codes →