Area codes · +1
Area code 623
Area code 623 covers Phoenix, Arizona. We hold 2,547 allocated blocks for it across 1 rate centre, split 43% mobile, 37% landline and 19% VoIP.
The other area codes laid over 623
Area code 623 does not have Phoenix to itself. 2 other codes — 480, 602 — serve the same rate centres, laid over the same ground rather than dividing it. That is an overlay: a new code added when the old one ran out of numbers, covering the same streets. Two neighbours can hold different area codes, so the code says roughly when a number was issued rather than where it sits.
Each holds its own blocks and its own carrier mix, so a 623 number and a 480 number from the same street can report different line types. Filtering Phoenix by area code needs all 3 of them.
Arizona is split across 5 area codes — 480, 520, 602, 928, 623. By allocated blocks 623 is the 5th largest of them, holding 11% of the Arizona total.
Where 623 numbers are concentrated
Rate-centre names are reproduced as NANPA records them. The agency truncates them to ten characters, so longer names appear shortened elsewhere on this site.
| Rate centre | Blocks | Share of 623 |
|---|---|---|
| Phoenix | 2,541 | 100% |
Carriers holding the most 623 blocks
Onvoy359 blocks
Qwest Corporation322 blocks
T-Mobile USA, Inc.313 blocks
Verizon Wireless270 blocks
T-Mobile Usa, Inc.251 blocks
Comcast Ip Phone, Llc186 blocks
The largest holder, Onvoy, has 14% of the code.
These are original allocations. A number keeps its digits and its block when its subscriber moves network, so a ported 623 number still reports the carrier it started with. Closing that gap needs a live query against the routing database. How line type is derived.
Check a single 623 number, or run a whole list through the free cleaner — neither uploads anything.
Common questions
Where is area code 623?
Area code 623 covers Phoenix, Arizona. It is not the only code there: 480, 602 are overlays on the same rate centres, so a Phoenix, Arizona number can start with any of them.
Is a 623 number a mobile or a landline?
It can be either, and the digits do not say which. North American mobile and landline numbers share the same ranges, so the answer comes from the carrier holding the block. In 623 the split runs 43% mobile, 37% landline and 19% VoIP, so mobile is the most likely single answer.
Which carriers hold 623 numbers?
The largest holders are Onvoy, Qwest Corporation, T-Mobile USA, Inc.. That is the carrier the block was allocated to, which is not necessarily the network a given number sits on today.
How many 623 numbers are there?
The code holds 2,547 allocated blocks in our copy of the numbering plan. A block is 1,000 or 10,000 consecutive numbers depending on how deeply it has been pooled, so 623 covers on the order of 2,547,000 possible numbers — most of which have never been issued to anyone.