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Area code Verified Nov 1, 2026 · Source: NANPA

Area code 738 – California

738 has served California since 2024, split from 323. It is still largely empty: 30 of 786 number blocks allocated. Onvoy / Inteliquent holds 63.3% of those blocks, which is unusually concentrated for a US area code. It shares its geography with overlay codes 213, 323, so local calls take all ten digits. Spam complaints are comparatively rare: 30 in the 33 days to 30 October 2026, 396th of the 422 codes with five or more complaints.

State
California
In service since
2024
Time zone
Pacific
Shares area with
213, 323

Who holds 738 number blocks

Share of the 30 assigned NXX blocks (3.8% of the 786 possible), across 8 carriers. This is share of number blocks, not of subscribers.

  • Onvoy63.3%
  • Other CLEC / VoIP20%
  • T-Mobile6.7%
  • AT&T3.3%
  • Dish3.3%
  • 8x83.3%

Spam complaints naming 738

FTC Do Not Call complaints where the caller ID was a 738 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.

30 complaints in 33 days
#396 of 422 ranked codes

Rate centers in 738

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 15.

LSAN DA 065
LSAN DA 043
LSAN DA 102
LSAN DA 132
LSAN DA 082

Timeline

  1. 2024 738 goes into service, split from or overlaid on 323.

More about 738

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 30 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 738 vs 213 Same area, different code – age, capacity and complaints side by side 738 vs 323 Same area, different code – age, capacity and complaints side by side

Frequently asked about 738

What state is area code 738?

California. It covers the same area as 213/323/738.

Is a call from 738 a scam?

Not by itself. 738 drew 30 FTC complaints in the 33 days to 30 October 2026, 396th 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 738 numbers?

Onvoy / Inteliquent holds the largest share of assigned number blocks at 63.3%. 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 738?

NANPA records the local dialing plan for 738 as “1+10D”.

Sources and verification

NANPA dialing note for this code: “1+10D”. Reviewed by the data desk. Spotted an error? Request a correction.

Nearby and related

323 California213 California323 California