---
title: "Area code 951: California, United States"
url: "https://lookvalid.com/area-code/951.md"
canonical_url: "https://lookvalid.com/area-code/951"
last_updated: "2026-10-23"
type: "reference"
summary: "Area code 951 serves California, United States. Number formats, numbering rules, a live phone validator and the other codes in California."
---

# Area code 951: California, United States

Area code 951 serves California, United States. Number formats, numbering rules, a live phone validator and the other codes in California.

NANPA lists 689 central office codes (prefixes) in use in area code 951, held by 35 holders across 21 rate centers.
T-Mobile USA holds the most prefixes, 120 (17%). 78% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
The FCC unwanted-call data has 2,973 complaints on file for 2,270 numbers in 951, most often filed as "Unwanted Calls". These are consumer reports, not findings.

## Facts

- In service since: 2004-07-17
- Time zone: Pacific (P)
- Prefixes in use: 689
- Pooled prefixes: 538 (78%)
- Rate centers: 21
- Companies holding prefixes: 35
- Assignment dates on file: 2001-01-26 to 2026-07-21 (395 prefixes)
- ZIP codes in its places: 42

## Rate centers

| Rate center | Prefixes | Share |
| --- | --- | --- |
| RIVERSIDE | 148 | 21% |
| CORONA | 88 | 13% |
| TEMECULA | 57 | 8% |
| PERRIS | 54 | 8% |
| MORENO | 52 | 8% |
| ARLINGTON | 49 | 7% |
| MURRIETA | 39 | 6% |
| HEMT HEMT | 37 | 5% |
| 13 other rate centers | 165 | 24% |

## Carriers

| Holder | Prefixes | Share |
| --- | --- | --- |
| T-Mobile USA | 120 | 17% |
| Verizon Wireless | 98 | 14% |
| New Cingular Wireless PCS | 76 | 11% |
| Pacific Bell | 75 | 11% |
| Frontier California | 69 | 10% |
| Onvoy | 42 | 6% |
| 29 other carriers | 209 | 30% |

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

- 1992-11-14: Area code 909, named as the parent of 951 in the NANPA report, was in service.
- 2004-07-17: Area code 951 went into service.

## Nearest area codes

The area codes closest to 951, measured between the centers of the ZIP code places they serve, are 909 (about 22 miles), 949 (about 29 miles), 657 (about 32 miles), 714 (about 32 miles) and 840 (about 33 miles).

## ZIP codes

42 ZIP codes fall in places that have a rate center in this area code. The places with the most are Riverside, CA (17 ZIP codes), Corona, CA (7 ZIP codes) and Temecula, CA (5 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

2,973 complaints for 2,270 numbers. Numbers whose latest complaint falls in each year:

- 2023: 119
- 2024: 119
- 2025: 146

## Questions

### Where is area code 951?

NANPA assigns area code 951 to California, United States.

### In which state does area code 951 sit?

California. 951 is one of 41 area codes the NANPA table assigns to the state.

### Which places does area code 951 cover?

The places with the most ZIP codes among the rate centers in 951 are Riverside, CA, Corona, CA and Temecula, CA. The rate center list on this page shows all of them.

### Who owns area code 951?

NANPA assigns area codes. Within 951, T-Mobile USA holds the most prefixes, 120 prefixes or 17%.

### Which time zone does 951 use?

The NANPA NPA report lists the time zone for 951 as Pacific (P).

### What year did 951 enter service?

The NANPA NPA report gives an in-service date of 2004-07-17, so 951 has been in use since 2004.

### Does area code 951 have an overlay?

The NANPA NPA report lists no other area code in an overlay with 951.

### Which area codes are nearest to 951?

The area codes closest to 951, measured between the centers of the ZIP code places they serve, are 909 (about 22 miles), 949 (about 29 miles), 657 (about 32 miles), 714 (about 32 miles) and 840 (about 33 miles).

### How many prefixes does area code 951 have?

NANPA's report dated 2026-10-17 lists 689 prefixes in service in 951, spread over 21 rate centers and 35 holders.

### Are there complaints about 951 numbers?

The FCC data on file has 2,973 complaints for 2,270 numbers in 951. 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).