---
title: "Area code 712: Iowa, United States"
url: "https://lookvalid.com/area-code/712.md"
canonical_url: "https://lookvalid.com/area-code/712"
last_updated: "2026-10-23"
type: "reference"
summary: "Area code 712 serves Iowa, United States. Number formats, numbering rules, a live phone validator and the other codes in Iowa."
---

# Area code 712: Iowa, United States

Area code 712 serves Iowa, United States. Number formats, numbering rules, a live phone validator and the other codes in Iowa.

NANPA lists 631 central office codes (prefixes) in use in area code 712, held by 111 holders across 244 rate centers.
Verizon Wireless holds the most prefixes, 68 (11%). 68% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
The FCC unwanted-call data has 2,323 complaints on file for 2,020 numbers in 712, most often filed as "Unwanted Calls". These are consumer reports, not findings.

## Facts

- In service since: 1947-01-01
- Time zone: Central (C)
- Prefixes in use: 631
- Pooled prefixes: 432 (68%)
- Rate centers: 244
- Companies holding prefixes: 111
- Assignment dates on file: 2001-01-18 to 2026-07-28 (258 prefixes)
- ZIP codes in its places: 223

## Rate centers

| Rate center | Prefixes | Share |
| --- | --- | --- |
| SIOUX CITY | 72 | 11% |
| COUNCILBLF | 29 | 5% |
| SERGENTBLF | 13 | 2% |
| SPENCER | 11 | 2% |
| LE MARS | 10 | 2% |
| CARROLL | 9 | 1% |
| HARLAN | 8 | 1% |
| STORM LAKE | 8 | 1% |
| 236 other rate centers | 471 | 75% |

## Carriers

| Holder | Prefixes | Share |
| --- | --- | --- |
| Verizon Wireless | 68 | 11% |
| Qwest | 64 | 10% |
| Windstream Iowa Communications, INC. - North | 48 | 8% |
| New Cingular Wireless PCS | 42 | 7% |
| Onvoy | 31 | 5% |
| Frontier Communications Of Iowa | 24 | 4% |
| 105 other carriers | 354 | 56% |

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 712 went into service.

## Nearest area codes

The area codes closest to 712, measured between the centers of the ZIP code places they serve, are 515 (about 85 miles), 531 (about 101 miles), 402 (about 107 miles), 641 (about 116 miles) and 507 (about 142 miles).

## ZIP codes

223 ZIP codes fall in places that have a rate center in this area code. The places with the most are Sioux City, IA (9 ZIP codes), Harlan, IA (2 ZIP codes) and Red Oak, IA (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

2,323 complaints for 2,020 numbers. Numbers whose latest complaint falls in each year:

- 2023: 150
- 2024: 131
- 2025: 217

## Questions

### Where is area code 712?

NANPA assigns area code 712 to Iowa, United States.

### In which state does area code 712 sit?

Iowa. 712 is one of 5 area codes the NANPA table assigns to the state.

### Which places does area code 712 cover?

The places with the most ZIP codes among the rate centers in 712 are Sioux City, IA, Harlan, IA and Red Oak, IA. The rate center list on this page shows all of them.

### Who owns area code 712?

NANPA assigns area codes. Within 712, Verizon Wireless holds the most prefixes, 68 prefixes or 11%.

### Which time zone does 712 use?

The NANPA NPA report lists the time zone for 712 as Central (C).

### What year did 712 enter service?

The NANPA NPA report gives an in-service date of 1947-01-01, so 712 has been in use since 1947.

### Does area code 712 have an overlay?

The NANPA NPA report lists no other area code in an overlay with 712.

### Which area codes are nearest to 712?

The area codes closest to 712, measured between the centers of the ZIP code places they serve, are 515 (about 85 miles), 531 (about 101 miles), 402 (about 107 miles), 641 (about 116 miles) and 507 (about 142 miles).

### How many prefixes does area code 712 have?

NANPA's report dated 2026-10-17 lists 631 prefixes in service in 712, spread over 244 rate centers and 111 holders.

### Are there complaints about 712 numbers?

The FCC data on file has 2,323 complaints for 2,020 numbers in 712. 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).