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US area code · California

Area code 738

Where the 738 area code is, its overlay and how to dial a +1 738 number from anywhere.

CoversCaliforniaTime zonePacific (PT)TypeOverlay
Quick answer

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.

StateCalifornia
Time zonePacific (PT)
TypeOverlay
10-digit dialingRequired
In service since16-Mar-2023

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.

Overlay 738 shares its region

Several area codes cover the same geographic area, so two neighbours can have different codes. Because of the overlay, you must dial all 10 digits (area code + number) even for local calls.

How to dial a 738 number

From abroad+1 738 555-0123
Within the US / Canada1 738 555-0123
Locally (same area)738 555-0123

Other 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.

Missed a call from +1 738?

In the 30 days to September 24, 2026, 14 unwanted calls showing a 738 number were reported to the US Federal Trade Commission, 79% of them recorded messages or robocalls. That puts 738 at #401 of 670 area codes reported.

Dropped call or no message6
Other6
Medical & prescriptions1
Before you call back
  • If you do not know anyone in California, do not call back: a genuine caller will leave a message or send a text.
  • Scammers fake the number shown on caller ID, so a 738 number can hide a caller anywhere in the world.
  • Never give a code received by text or a bank detail to an unknown caller. In the US, calls can be reported at reportfraud.ftc.gov.

Who issues +1 738 numbers

Phone companies hold blocks of numbers in each area code. The main holders in 738:

Onvoy, LLC 16 14Wide Voice, LLC 4T-Mobile USA, Inc. 2Opentact Inc. 1Boost Subscriberco L.L.C. 1

About 5% of the 40 prefixes in use belong to mobile carriers: a 738 number is often a cell phone, and it may have moved to another carrier since.

Sources: FTC Do Not Call reported calls (numbers as reported by consumers, not verified), NANPA central office code assignments.

All US area codes United States +1 Map of area code 738 — cities & rate centres