South Dakota Area Codes

Area codes: 1
ZIP codes: 385
Cities & towns: 363
Counties: 66

Every area code in South Dakota

All South Dakota area codes, what each primarily serves, and which share ground with another.
Area code	Primarily serves	In service
605	Sioux Falls	1947

Which codes share the same ground

No South Dakota code shares its territory with another — each covers its own area, so an area code here still corresponds to a single part of the state.

Where South Dakota's communities sit

Each point is a South Dakota community, plotted from its record coordinates. The outline is the convex envelope of those points — a footprint, not a boundary.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Largest South Dakota cities and their codes

largest 25

Scope every area code assigned to South Dakota. Source LocalCallingGuide NPA list (2026-07 NPA list) and geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot). Updated 16 July 2026. Overlay relationships come from the numbering-plan authority; the city match is computed.