Prefix 619-603 — National City, CA

NANPA CO code assignment, current as of July 28, 2026.

Area code
619
Prefix (NXX)
603
Rate center
National City
State
California
Time zone
Pacific
Code holder
T-MOBILE USA, INC.
OCN
6529
Pooled
Yes (thousands-block pooling)
Assigned
2019-06-24
LATA
732

The 619-603 prefix belongs to area code 619 and is anchored to the National City rate center (CA). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.

National City is part of the San Diego-Cula Vista-Carlsbad, CA Metropolitan Statistical Area. For routing purposes it sits in LATA 732. Numbers here keep Pacific time.

The assigned code holder is T-MOBILE USA, INC., operating company number 6529, assigned June 24, 2019. This is a pooled prefix — expect numbers within it to be split across more than one carrier in 1,000-number blocks.

Caller ID showing 619-603 is not proof the call came from National City: spoofing and porting both detach numbers from their origin. To verify a caller, hang up and dial the organization's published number, and report suspicious calls to the FTC.

Neighboring prefixes

Prefixes adjacent to 619-603
PrefixRate centerCode holder
619-600 Chula Vista T-MOBILE USA, INC.
619-601 Chula Vista BANDWIDTH.COM CLEC, LLC - CA
619-602 San Diego:san Diego Da T-MOBILE USA, INC.
619-604 San Diego:san Diego Da ONVOY, LLC - CA
619-605 San Diego:linda Vista Da COMCAST PHONE OF CALIFORNIA, LLC
619-606 San Diego:san Diego Da NEW CINGULAR WIRELESS PCS, LLC

FAQ

Where is 619-603 located?

The prefix is assigned to the National City rate center in CA, area code 619. It is part of the San Diego-Cula Vista-Carlsbad, CA Metropolitan Statistical Area.

Which company owns 619-603 numbers?

T-MOBILE USA, INC. holds the code, but the prefix is pooled — individual thousands-blocks can be assigned to other carriers, and numbers may be ported to any provider.

Is a call from 619-603 safe to answer?

The prefix itself says nothing about the caller. Legitimate National City businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.