NumberingData
Methodology Download the data
Area code Verified Nov 1, 2026 · Source: NANPA

Area code 520 – Arizona

520 has served Arizona since 1995, split from 602. 699 of its 786 number blocks are allocated (89%). No carrier dominates: Lumen / CenturyLink 33.2%, Verizon 18.6%, Other CLEC / VoIP 12.4%. It is also among the most imitated codes in spam calls: 1,592 FTC complaints named a 520 caller ID in the 33 days to 30 October 2026, ranking 6th of 422 ranked codes.

State
Arizona
In service since
1995
Time zone
Mountain
Shares area with
No overlay

Who holds 520 number blocks

Share of the 699 assigned NXX blocks (88.9% of the 786 possible), across 52 carriers. This is share of number blocks, not of subscribers.

  • Lumen33.2%
  • Verizon18.6%
  • T-Mobile13.6%
  • Other CLEC / VoIP10.6%
  • AT&T9.7%
  • Onvoy6.7%
  • Bandwidth2.4%
  • Allstream1.4%
  • Comcast1%
  • Charter0.7%
  • Peerless0.6%
  • Telnyx0.4%
  • Dish0.3%
  • Windstream0.1%
  • Spok0.1%
  • Twilio0.1%
  • Vonage0.1%
  • 8x80.1%

Spam complaints naming 520

FTC Do Not Call complaints where the caller ID was a 520 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.

1,592 complaints in 33 days
#6 of 422 ranked codes

Rate centers in 520

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. Showing the largest 5 of 37.

TUCSON400
SIERRAVIST70
CASAGRANDE67
NOGALES32
WILLCOX18

Timeline

  1. 1995 520 goes into service, split from or overlaid on 602.

More about 520

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.

All prefixes Every one of the 699 assigned NXX blocks, with the holder of each Local time Zone, UTC offset, clock changes and a live clock Spam complaints How often the code appears in FTC complaints, and what to do Carriers Who holds the number blocks, and why that is not who serves them

Frequently asked about 520

What state is area code 520?

Arizona.

Is a call from 520 a scam?

520 is one of the most complained-about codes in the country – 1,592 FTC complaints in the 33 days to 30 October 2026, 6th of 422 ranked codes. Most of those calls are spoofed: the caller fakes a local-looking number because it gets answered more often. Look up the specific number rather than judging by the code.

Which carrier owns 520 numbers?

Lumen / CenturyLink holds the largest share of assigned number blocks at 33.2%. 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 520?

Yes – ten digits for local calls in 520, because it shares its area with another code.

Sources and verification

NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.

Nearby and related

602 Arizona