The South Dakota area code
Every active code: tap any card for its full guide, who called, cities and ZIPs, map, spam patterns and local time.
Got a call from a South Dakota number you don’t recognize?Open that code’s guide above for its full prefix lookup. AT&T ActiveArmor® blocks spam automatically, included with AT&T wireless plans.
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Included with AT&T wireless plans. Requires compatible device/service and download of the AT&T ActiveArmor® app. Other terms & restrictions apply. May not detect all threats and may block wanted calls. Some features require Advanced mobile security ($7/mo.). See terms.
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Service good for 30 days. Data: Limited to 100GB of data and 25GB of hotspot data. No additional data is available after limit is reached. Video is limited to SD quality. Talk & Text: Includes unlimited talk & text within the U.S. and unlimited text from the U.S. to over 230 countries. Limits: One trial per user. An unlocked, GSM-compatible iOS or Android phone with eSIM capability is required. You’ll receive a trial phone number that belongs to AT&T and is not available to be ported to another carrier or otherwise retained. Trial plan features and details may differ from or be unavailable in other AT&T plans. U.S. only. All terms subject to change at any time.
South Dakota area codes by city
The largest South Dakota communities and the area code that serve them. Every city links to its local AT&T internet page.
| City | Area code(s) |
|---|---|
| Sioux Falls | 605 |
| Aberdeen | 605 |
| Brookings | 605 |
| Huron | 605 |
| Mitchell | 605 |
| Pierre | 605 |
| Rapid City | 605 |
| Spearfish | 605 |
| Watertown | 605 |
| Yankton | 605 |
How South Dakota got its codes
Every South Dakota area code, in the order it entered service. Splits carved new regions; added codes overlay existing ones, which is why ten-digit dialing is standard.
| In service | Code | How it arrived |
|---|---|---|
| 1947 | 605 | One of the original area codes of 1947 |
Source: NANPA NPA database, July 2026. Regenerated monthly.
South Dakota area code map
One code covers all of South Dakota. Click or tap the map to open its full guide.
How South Dakota’s codes work
How South Dakota works
605 is the whole map: every county in South Dakota, one code.
One code, statewide
Every local number in South Dakota starts with 605. From out of state, dial 1 605 and the seven-digit number.
Reading the map
The whole state is one territory. Click or tap the map to open the 605 guide.
Every code links to a full guide.
Who called, cities and ZIPs, maps and spam patterns.
Take the map with youPoster format of the South Dakota area code map with a QR code back to this page.↓ Download the printable PDF
Internet, wireless & stores across the state
AT&T home internet in South Dakota
AT&T home internet is available across South Dakota, checked address by address; every area code guide above lists its cities and what’s offered there.
AT&T Fiber: Ltd. avail/areas. Speeds based on wired connection. Actual speeds vary. For 5-GIG, single device wired speed maximum 4.7Gbps. For more info., visit att.com/speed101.
Start with home internet in South Dakota, or pair it with wireless in an internet + wireless bundle.
AT&T wireless in South Dakota
AT&T’s 5G network covers most of South Dakota. ActiveArmor® spam blocking is included with every unlimited plan, your number stays yours when you move between South Dakota codes, and great cell phone deals in South Dakota are a tap away.
AT&T may temporarily slow data speeds if the network is busy. 5G req’s compatible plan & device. Coverage not available everywhere. Learn more at att.com/5Gforyou.
AT&T stores across South Dakota
From the Sioux Falls metro to Mitchell, Aberdeen and beyond, walk in for switching, porting, upgrades and hands-on help. Every area code guide lists its nearest stores.
Find stores in: Sioux Falls · Mitchell · Aberdeen · Huron · Brookings
