738 area code
Where the 738 area code is, its overlay and how to dial a +1 738 number from anywhere.
The 738 area code is in California, United States (Pacific (PT)). To call from abroad: +1 738 555-0123. It is an overlay, so all 10 digits are dialled.
The 738 area code is a geographic North American Numbering Plan (NANP) code covering California. It has been in service since 16-Mar-2023 and sits in the Pacific (PT) time zone.
How to dial a 738 number
+1 738 555-01231 738 555-0123738 555-0123Other California area codes
Frequently asked questions
Where is the 738 area code?
The 738 area code is in California, United States (Pacific (PT)).
Is 738 an overlay area code?
Yes. 738 overlays the same region as 213, 323, so callers dial all 10 digits.
Do I have to dial 10 digits for 738?
Yes — dial the area code plus the seven-digit number.
How do I call a 738 number from another country?
Dial your exit code (or +), then 1, then 738, then the number: +1 738 555-0123.
Source: NANPA numbering plan. An area code covers a region, not a precise address — a 738 number does not pinpoint a street or ZIP code.
Number holders in area code 738
Each prefix (the three digits after the area code) is assigned by NANPA to one telephone company. 40 prefixes are in use in 738, shared by 8 companies. The largest holders:
| Company | Prefixes | Share |
|---|---|---|
| Onvoy, LLC | 16 | 40% |
| 14 | 35% | |
| Wide Voice, LLC | 4 | 10% |
| T-Mobile USA, Inc. | 2 | 5% |
| Opentact Inc. | 1 | 3% |
| Boost Subscriberco L.L.C. | 1 | 3% |
Source: NANPA central office code assignments. A number keeps its original prefix when it is ported to another carrier.
Complaints about 738 numbers
- Reports to the FTC, last 30 days
- 14
- Recorded messages or robocalls
- 79%
- Rank among area codes
- #401 of 670
- Most reported subjects
- Dropped call or no message (6)
- Other (6)
- Medical & prescriptions (1)
Period Aug 26 – Sep 24, 2026. These are the numbers shown on the caller ID of the reported calls; many are spoofed and do not belong to the real caller.
Source: US Federal Trade Commission, Do Not Call reported calls data (daily files).
All US area codes United States +1 Map of area code 738 — cities & rate centres