Area code
623
623 is a United States area code. Under the North American Numbering Plan it belongs to Arizona, which has 5 area codes in total.
Validate a number in 623
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.
Digits with or without punctuation work. Numbers outside the US are read with the +country code.
Area code 623 at a glance
NANPA lists 311 central office codes (prefixes) in use in area code 623, held by 28 holders across 1 rate center.
| Fact | Value |
|---|---|
| In service since | 1999-03-01 |
| Time zone | Mountain (M) |
| Assigned overlays | 602 (1947-01-01), 480 (1999-03-01) |
| Prefixes in use | 311 |
| Pooled prefixes | 223 (72%) |
| Rate centers | 1 |
| Companies holding prefixes | 28 |
| Assignment dates on file | 2001-01-18 to 2026-08-07 (164 prefixes) |
| ZIP codes in its places | 77 |
Rate centers in area code 623
The largest rate center is PHOENIX, with 311 prefixes (100%).
| Rate center | Prefixes | Share |
|---|---|---|
| PHOENIX | 311 | 100% |
Who holds the prefixes in 623
Qwest holds the most prefixes, 97 (31%). 72% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
| Holder | Prefixes | Share |
|---|---|---|
| Qwest | 97 | 31% |
| T-Mobile USA | 39 | 13% |
| Verizon Wireless | 31 | 10% |
| Onvoy | 28 | 9% |
| New Cingular Wireless PCS | 22 | 7% |
| Mcimetro Access Transmission Services | 13 | 4% |
| 22 other carriers | 81 | 26% |
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 623
- 1947-01-01 Area code 602, named as the parent of 623 in the NANPA report, was in service.
- 1999-03-01 Area code 623 went into service.
Area codes nearest to 623
Distance is measured between the centers of the ZIP code places each area code serves, so it is a rough guide.
Overlay codes in the same area
ZIP codes in area code 623
77 ZIP codes fall in places that have a rate center in this area code.
| Place | ZIP codes |
|---|---|
| Phoenix, AZ | 77 |
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 623 numbers
2,103 FCC complaints are on file for 1,554 numbers in 623, most often filed as "Unwanted Calls". These are unverified consumer reports.
| Year of latest complaint | Numbers |
|---|---|
| 2023 | 81 |
| 2024 | 98 |
| 2025 | 110 |
Other area codes in Arizona
Arizona is one state with 5 area codes in the NANPA table. 623 is one of them.
Next to 623 in the numbering table
These are the codes just before and after 623 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 623 was first assigned in Arizona. 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 Arizona next to a 623 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 623
Where is area code 623?
NANPA assigns area code 623 to Arizona, United States.
In which state does area code 623 sit?
Arizona. 623 is one of 5 area codes the NANPA table assigns to the state.
Which places does area code 623 cover?
The places with the most ZIP codes among the rate centers in 623 are Phoenix, AZ. The rate center list on this page shows all of them.
Who owns area code 623?
NANPA assigns area codes. Within 623, Qwest holds the most prefixes, 97 prefixes or 31%.
Which time zone does 623 use?
The NANPA NPA report lists the time zone for 623 as Mountain (M).
What year did 623 enter service?
The NANPA NPA report gives an in-service date of 1999-03-01, so 623 has been in use since 1999.
Does area code 623 have an overlay?
Yes. 602 (in service 1947-01-01) and 480 (in service 1999-03-01) share the same area with 623, so numbers from all of them are local to each other.
Which area codes are nearest to 623?
The area codes closest to 623, measured between the centers of the ZIP code places they serve, are 520 (about 75 miles), 928 (about 80 miles), 702 (about 253 miles), 725 (about 253 miles) and 760 (about 279 miles).
How many prefixes does area code 623 have?
NANPA's report dated 2026-10-17 lists 311 prefixes in service in 623, spread over 1 rate center and 28 holders.
Are there complaints about 623 numbers?
The FCC data on file has 2,103 complaints for 1,554 numbers in 623. 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.