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738

Area code 738

California, United States

National (738) 555-0123, E.164 +17385550123

How the 41 central office codes (exchanges) of area code 738 were allocated, from the North American Numbering Plan's records: to which carrier, as which line type. A 738 number is mobile, fixed line or VoIP according to its exchange, the three digits after the area code; the allocation is the original one (below).

At a glance

Country code
+1
State
CA
Exchanges on record
41
Carriers on record
8
Exchanges of 738 by the line type they were allocated as
  • Mobile 4 (10%)
  • Fixed line 5 (12%)
  • VoIP 18 (44%)
  • No line type on record 14 (34%)
  • 41 exchanges on record

Most exchanges: Onvoy 16, Wide Voice 4, T-Mobile 2.

Check a number

Valid fixed line or mobile number in the United States.

+1
country code
738
area code
5550123
subscriber number
CountryUnited States numbering plan
Line typeFixed line or mobile
Carrier the block was allocated toNo carrier on record for this prefix
E.164+17385550123
International+1 738-555-0123
National(738) 555-0123
RFC 3966tel:+1-738-555-0123

Source: North American Numbering Plan Administrator (NANPA); Canadian Numbering Administrator (CNAC); National numbering plan: United States (ITU)

The example is 738-555-0123: 555-0100 to 555-0199 are set aside for fictional use in every area code.

The exchange map

Every exchange of 738, by the line type it was allocated as

One cell per exchange: blocks 738 2xx to 738 9xx; in each block the row is the tens digit, the column the units digit.

738 2xx738 3xx738 4xx738 5xx738 6xx738 7xx738 8xx738 9xx
  • Mobile 4
  • Fixed line 5
  • VoIP 18
  • No line type on record 14
  • Not on record 759

Formats and patterns

E.164+17385550123
International+1 738-555-0123
National(738) 555-0123
RFC 3966 (tel: URI)tel:+1-738-555-0123

Any 738 number, in E.164

^\+1738[2-9]\d{6}$

+1, the area code, a central office code that does not start with 0 or 1, then four digits.

Mobile exchanges (4 on record)

^\+1738(?:2(?:0[02]|12)|338)\d{4}$

Fixed line exchanges (5 on record)

^\+1738(?:3(?:00|33)|777|888|999)\d{4}$

VoIP exchanges (18 on record)

^\+1738(?:2(?:0[13-9]|10|22)|444|529|666|738|8[08]0|9(?:00|98))\d{4}$

The exchange patterns follow the original allocations; a number ported since keeps its digits but not necessarily its carrier or its line type.

Carriers and their exchanges

Every carrier holding exchanges in 738, with the exchanges allocated to it (the three digits after the area code).

CarrierExchangesMobileFixed lineVoIPExchanges held
Onvoy160016201, 203–210, 222, 444, 529, 666, 800, 900, 998
Wide Voice4040333, 777, 888, 999
T-Mobile2200200, 202
8x81001880
AT&T1100212
Dish Wireless1100338
Exiant1001738
Opentact1010300

Questions developers ask

Where is area code 738?
Area code 738 is in California, in the United States: all 41 of its exchanges on record are there. From abroad it is dialled +1 738, then the seven-digit number.
Is a 738 number mobile or landline?
Either: in the North American Numbering Plan the line type belongs to the exchange (the three digits after the area code), not to the area code. Of the 41 exchanges on record in 738, 4 (10%) were allocated as mobile, 5 (12%) as fixed line, 18 (44%) as VoIP and 14 (34%) have no line type on record. A number can have been ported since, to another carrier and even to another line type.
Which carriers have numbers in area code 738?
8 carriers hold exchanges in 738 on record; the most: Onvoy (16), Wide Voice (4) and T-Mobile (2). These are the original allocations: with number portability, a number may be served by another carrier today, which only a live carrier lookup (an HLR or MNP query) can tell.
How do I validate a 738 phone number?
In E.164 a 738 number matches ^\+1738[2-9]\d{6}$: +1, the area code, a central office code that does not start with 0 or 1, then four digits. Written nationally it reads (738) 555-0123. The exchange patterns on this page narrow it to the exchanges allocated as mobile, fixed line or VoIP.