Area code
951
951 is a United States area code. Under the North American Numbering Plan it belongs to California, which has 41 area codes in total.
Validate a number in 951
Paste a full number and the tool checks it against the numbering plan. It returns the standard formats, the line type the plan assigns and the area code region.
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Area code 951 at a glance
NANPA lists 689 central office codes (prefixes) in use in area code 951, held by 35 holders across 21 rate centers.
| Fact | Value |
|---|---|
| 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 in area code 951
| 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% |
Who holds the prefixes in 951
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.
| 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. Find which carrier a number is on, or browse the prefix holders.
History of area code 951
- 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.
Area codes nearest to 951
Distance is measured between the centers of the ZIP code places each area code serves, so it is a rough guide.
ZIP codes in area code 951
42 ZIP codes fall in places that have a rate center in this area code.
| Place | ZIP codes |
|---|---|
| Riverside, CA | 17 |
| Corona, CA | 7 |
| Temecula, CA | 5 |
A ZIP code and an area code are unrelated systems. A ZIP code can sit in more than one area code, and an area code spans many ZIP codes.
Complaints on file for 951 numbers
2,973 FCC complaints are on file for 2,270 numbers in 951, most often filed as "Unwanted Calls". These are unverified consumer reports.
| Year of latest complaint | Numbers |
|---|---|
| 2023 | 119 |
| 2024 | 119 |
| 2025 | 146 |
Other area codes in California
California is one state with 41 area codes in the NANPA table. 951 is one of them.
- 209
- 213
- 279
- 310
- 323
- 341
- 350
- 357
- 369
- 408
- 415
- 424
- 442
- 510
- 530
- 559
- 562
- 619
- 626
- 628
- 650
- 657
- 661
- 669
- 707
- 714
- 738
- 747
- 760
- 805
- 818
- 820
- 831
- 837
- 840
- 858
- 909
- 916
- 925
- 949
Next to 951 in the numbering table
These are the codes just before and after 951 when all are sorted by number. They are neighbours on the list, not necessarily on the map.
What the area code does and does not tell you
A number that starts with 951 was first assigned in California. That is a fact about where the number began, and it is a useful hint when you check a form entry, for example a billing address in California next to a 951 phone number.
It does not show where the person is today. A number stays with its owner after a move or a change of provider (number portability), and mobile numbers travel with the handset. The area code also cannot tell you whether the line is active, who the carrier is, or whether the number is mobile or fixed: the plan shares those ranges. Read more about the area code, the numbering plan and line type.
Check numbers in bulk with the API
| Product | Credits | Docs |
|---|---|---|
| Phone Numbering-Plan Validation | 1 credit per valid number | API docs |
| Phone Intelligence (carrier and line status) | 1 credit per check (invalid numbers outside the US and Canada are free) | Product page |
Questions about area code 951
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.
Area code assignments: North American Numbering Plan Administrator NPA report, file dated 10/17/2026, retrieved 2026-10-17. Source file. New codes are assigned several times a year. Prefixes, rate centers, holders, time zone, in-service date and overlays: NANPA central office code report dated 2026-10-17 and NPA report dated 2026-10-18. Complaints: FCC consumer complaints open data, fetched 2026-10-17. ZIP code places: Postal code places and coordinates: GeoNames (geonames.org), licensed CC BY 4.0.