---
title: "Area code 605: South Dakota, United States"
url: "https://lookvalid.com/area-code/605.md"
canonical_url: "https://lookvalid.com/area-code/605"
last_updated: "2026-10-23"
type: "reference"
summary: "Area code 605 serves South Dakota, United States. Number formats, numbering rules, a live phone validator and the other codes in South Dakota."
---

# Area code 605: South Dakota, United States

Area code 605 serves South Dakota, United States. Number formats, numbering rules, a live phone validator and the other codes in South Dakota.

NANPA lists 744 central office codes (prefixes) in use in area code 605, held by 89 holders across 269 rate centers.
Qwest holds the most prefixes, 104 (14%). 49% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
The FCC unwanted-call data has 1,809 complaints on file for 1,439 numbers in 605, most often filed as "Unwanted Calls". These are consumer reports, not findings.

## Facts

- In service since: 1947-01-01
- Time zone: CM
- Prefixes in use: 744
- Pooled prefixes: 365 (49%)
- Rate centers: 269
- Companies holding prefixes: 89
- Assignment dates on file: 2001-01-16 to 2026-08-04 (256 prefixes)
- ZIP codes in its places: 217

## Rate centers

| Rate center | Prefixes | Share |
| --- | --- | --- |
| SIOUX FLS | 92 | 12% |
| RAPID CITY | 50 | 7% |
| ABERDEEN | 22 | 3% |
| SPEARFISH | 20 | 3% |
| WATERTOWN | 17 | 2% |
| HURON | 15 | 2% |
| PIERRE | 15 | 2% |
| YANKTON | 14 | 2% |
| 261 other rate centers | 499 | 67% |

## Carriers

| Holder | Prefixes | Share |
| --- | --- | --- |
| Qwest | 104 | 14% |
| Verizon Wireless | 100 | 13% |
| New Cingular Wireless PCS | 81 | 11% |
| Midcontinent Communications. | 34 | 5% |
| Bluepeak | 32 | 4% |
| Venture Communications Cooperative | 30 | 4% |
| 83 other carriers | 363 | 49% |

A prefix holder is the company a code was assigned to, not necessarily a number's current carrier, because numbers can be ported to another company.

## History

- 1947-01-01: Area code 605 went into service.

## Nearest area codes

The area codes closest to 605, measured between the centers of the ZIP code places they serve, are 320 (about 221 miles), 701 (about 222 miles), 712 (about 233 miles), 308 (about 235 miles) and 402 (about 238 miles).

## ZIP codes

217 ZIP codes fall in places that have a rate center in this area code. The places with the most are Rapid City, SD (4 ZIP codes), Aberdeen, SD (2 ZIP codes) and Brookings, SD (2 ZIP codes). A ZIP code and an area code are unrelated systems, so a ZIP code can sit in more than one area code and an area code spans many ZIP codes.

## Complaints on file

1,809 complaints for 1,439 numbers. Numbers whose latest complaint falls in each year:

- 2023: 82
- 2024: 102
- 2025: 69

## Questions

### Where is area code 605?

NANPA assigns area code 605 to South Dakota, United States.

### In which state does area code 605 sit?

South Dakota. 605 is one of 1 area code the NANPA table assigns to the state.

### Which places does area code 605 cover?

The places with the most ZIP codes among the rate centers in 605 are Rapid City, SD, Aberdeen, SD and Brookings, SD. The rate center list on this page shows all of them.

### Who owns area code 605?

NANPA assigns area codes. Within 605, Qwest holds the most prefixes, 104 prefixes or 14%.

### Which time zone does 605 use?

The NANPA NPA report lists the time zone for 605 as CM.

### What year did 605 enter service?

The NANPA NPA report gives an in-service date of 1947-01-01, so 605 has been in use since 1947.

### Does area code 605 have an overlay?

The NANPA NPA report lists no other area code in an overlay with 605.

### Which area codes are nearest to 605?

The area codes closest to 605, measured between the centers of the ZIP code places they serve, are 320 (about 221 miles), 701 (about 222 miles), 712 (about 233 miles), 308 (about 235 miles) and 402 (about 238 miles).

### How many prefixes does area code 605 have?

NANPA's report dated 2026-10-17 lists 744 prefixes in service in 605, spread over 269 rate centers and 89 holders.

### Are there complaints about 605 numbers?

The FCC data on file has 1,809 complaints for 1,439 numbers in 605. They are unverified consumer reports. A number with no complaints on file is not proven safe.

Sources: NANPA central office code report dated 2026-10-17; NANPA NPA report dated 2026-10-18; FCC unwanted-call complaints, data fetched 2026-10-17; ZIP code places from GeoNames (CC BY 4.0).