Where is area code 605?
NANPA assigns 605 to South Dakota. The source report does not provide city-level coverage for this record, so this page does not guess a particular city. Browse other codes in South Dakota
Verified area-code information
605 Area Code
605 is an in-service United States area code assigned to South Dakota. It identifies a numbering region, not a caller’s current location.
Official Numbering RegionVerified NANPA Assignment
South DakotaArea Code 605
Country: United States•Time Zone: Central and Mountain•In Service: 01-Jan-1947
- Numbering country
- United States
- Area-code type
- Geographic
- Numbering region
- South Dakota
- Time-zone information
- Central and Mountain
- In service since
- 01-Jan-1947
View the official area-code maps ↗. Maps show numbering areas, not a caller’s location.
Time zones associated with 605
NANPA lists Central and Mountain for this numbering area. These are numbering-region time zones, not a caller’s current location.
Central time
Mountain time
An area code can span more than one time zone. Local daylight-saving rules may differ.
How do you dial a 605 number?
Use the North American country calling code +1 followed by the three-digit area code and seven-digit local number. For example, write the pattern as +1 605 XXX XXXX. Local dialing rules and charges depend on your location and provider. Check a supported dialing format or check NANPA’s 10-digit dialing list.
Assigned prefixes in 605
NANPA’s US report listed 743 assigned prefixes on 2026-09-29. These are code assignments, not a count of active phone numbers or proof of a caller’s current carrier. Search any US area code and prefix.
Top rate-center labels by assigned prefixes
| Rate center | Assigned prefixes |
|---|---|
| SIOUX FLS | 92 |
| RAPID CITY | 50 |
| ABERDEEN | 22 |
| SPEARFISH | 20 |
| WATERTOWN | 17 |
Top listed companies by assigned prefixes
| Assignment company | Assigned prefixes |
|---|---|
| QWEST CORPORATION | 104 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD | 100 |
| NEW CINGULAR WIRELESS PCS, LLC - IL | 81 |
| MIDCONTINENT COMMUNICATIONS. - SD | 34 |
| CLARITY TELECOM, LLC DBA BLUEPEAK | 33 |
605 prefix lookup
743 assigned prefixes are listed for this area code. Search NANPA’s US central-office code assignments. The listed company and rate center describe an assignment; number portability means they cannot identify the current carrier, subscriber, or caller.
The area-code file loads when you search. The three-digit prefix stays in your browser.
Check a number with area code 605
Enter the full ten-digit number to see its structure and formatting. The check stays in your browser.
Check a 605 number
Enter a 10-digit +1 North American number. We check its structure and area-code record, not the caller’s identity or whether the line is active.
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Received an unfamiliar call?
The displayed number may be spoofed. Do not rely on an area code as proof of caller identity. If the caller claims to represent a business, end the call and contact that business using a number you found independently.
Common questions about 605
What time zone is area code 605 in?
605 is assigned to South Dakota, and the NANPA record associates it with Central and Mountain time. A phone number does not reveal its owner’s current time zone. The clock above uses a representative time zone for the numbering area.
Does 605 mean the caller is in South Dakota?
No. An area code is an assignment, and a person can travel, move, use internet calling, or display a spoofed number.
Can this page identify who called?
No. OfficialAreaCode has no live subscriber directory or spam-report database.