738 Area Code

Area Code Overview

Area code 738 is a geographic telephone area code in California that went into service on November 1, 2024. The geographic regions covered by this area code overlay has a population of approximately 3,983,297.

Overlay and Dialing Rules

  • Area Code: 738
  • State: California
  • Type: General Purpose Code
  • In Service Date: November 1, 2024
  • Overlay Complex: 213/323/738
  • Local Dialing Plan: This area requires you to dial 1 and the area code when calling locally.

Estimated Number of Assigned Phone Numbers in Area Code 738

This area code is ranked 360th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 39th out of 39.

99,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 738

Total assigned 99,000
Wireless
13,000 assigned
13.13%
Wireline and VoIP
83,000 assigned
83.84%
Other / Unclassified
3,000 assigned
3.03%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 738

Estimated assigned wireless phone numbers: 13,000

Numbers may later be ported to another carrier, but this chart reflects original number assignment, not current subscriber share.

T-Mobile 10,000 (76.92%)
Verizon Wireless 3,000 (23.08%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 738

Estimated assigned wireline and VoIP phone numbers: 83,000

Onvoy 57,000 (68.67%)
Wide Voice 22,000 (26.51%)
Bandwidth 2,000 (2.41%)
TERRA NOVA TELECOM INC. 2,000 (2.41%)

Other / Unclassified Assigned Numbering in Area Code 738

Estimated assigned other or unclassified phone numbers: 3,000

EXIANT COMMUNICATIONS LLC 3,000 (100.00%)

Cities and Towns in Area Code 738

These geographic regions are also served by area codes 213 and 323.

How These Figures Were Built

These figures are estimates based on public phone-number assignment records. They are meant to show the likely mix of assigned phone numbers associated with area code 738, not live customer counts.

Some providers may have assigned phone numbers tied to this area code even if they do not actively market or sell service locally. These figures reflect public number-assignment records, not confirmed local service availability.

They also do not reflect number portability at the individual phone-number level, so some numbers may now be used on a different network or by a different provider than the original assignment records suggest.

Population data and locality matching provided by GeoNames.

Last refreshed: April 15, 2026 6:22 pm