Area code 623 – Arizona
623 has served Arizona since 1999, split from 602. 314 of its 786 number blocks are allocated (40%). Lumen / CenturyLink is the largest holder with 35.4% of blocks, ahead of Verizon at 14.0%. It shares its geography with overlay codes 480, 602, so local calls take all ten digits. FTC complaints naming a 623 caller ID totalled 598 in the 33 days to 30 October 2026 (173rd of 422 ranked codes). All of its numbers sit in a single telephone rate center covering the whole area.
- State
- Arizona
- In service since
- 1999
- Time zone
- Mountain
Who holds 623 number blocks
Share of the 314 assigned NXX blocks (39.9% of the 786 possible), across 29 carriers. This is share of number blocks, not of subscribers.
- Lumen35.4%
- T-Mobile15%
- Verizon14%
- AT&T9.9%
- Onvoy9.2%
- Comcast3.5%
- Other CLEC / VoIP3.5%
- Allstream2.5%
- Bandwidth2.5%
- Charter1.9%
- Dish0.6%
- Peerless0.6%
- Windstream0.3%
- Telnyx0.3%
- VoIP Innovations0.3%
- 8x80.3%
Spam complaints naming 623
FTC Do Not Call complaints where the caller ID was a 623 number, 28 Sep – 30 Oct 2026 (33 days). Caller IDs on spam calls are frequently spoofed, so these are complaints about the code, not calls proven to originate in it.
Rate centers in 623
NANPA allocates number blocks to rate centers and records their names abbreviated to ten characters, so these are NANPA's codes rather than place names – CHAMPAURBN is Champaign-Urbana, NWYRCYZN01 is a New York City zone. We show them unchanged instead of guessing at the full names. This code has a single rate center covering its whole area.
Timeline
- 1999 623 goes into service, split from or overlaid on 602.
More about 623
Separate pages for the questions that need their own answer: what time it is there, what the complaint data says, who holds the number blocks, and how the code compares with the one it shares its area with.
Frequently asked about 623
What state is area code 623?
Arizona. It covers the same area as 480/602/623.
Is a call from 623 a scam?
Not by itself. 623 drew 598 FTC complaints in the 33 days to 30 October 2026, 173rd of 422 ranked codes – mid-pack or lower. Spam callers spoof caller IDs, so the only useful check is the full number.
Which carrier owns 623 numbers?
Lumen / CenturyLink holds the largest share of assigned number blocks at 35.4%. The rest is spread across 3 other carriers. This is share of number blocks, not of subscribers – people keep their numbers when they switch carriers.
Do I need to dial 10 digits in 623?
Yes – ten digits for local calls in 623, because it shares its area with another code.
Sources and verification
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 25 daily files 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.