Prefix 909-344 — Claremont, CA

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

Area code
909
Prefix (NXX)
344
Rate center
Claremont
State
California
Time zone
Pacific
Code holder
T-MOBILE USA, INC.
OCN
6529
Pooled
Yes (thousands-block pooling)
Assigned
2012-10-02
LATA
730

The 909-344 prefix belongs to area code 909 and is anchored to the Claremont rate center (CA). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.

Claremont is part of the Los Angeles-Long Beach-Anaheim, CA Metropolitan Statistical Area. For routing purposes it sits in LATA 730. Numbers here keep Pacific time.

The assigned code holder is T-MOBILE USA, INC., operating company number 6529, assigned October 2, 2012. 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 909-344 is not proof the call came from Claremont: 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 909-344
PrefixRate centerCode holder
909-341 Rialto TWC IP ENABLED SERVICES, LLC
909-342 Chino LEVEL 3 COMMUNICATIONS, LLC - CA
909-343 Arrowhead T-MOBILE USA, INC.
909-345 Diamond Bar BANDWIDTH.COM CLEC, LLC - CA
909-346 Fontana METROPCS NETWORKS, LLC
909-347 Fontana BANDWIDTH.COM CLEC, LLC - CA

FAQ

Where is 909-344 located?

The prefix is assigned to the Claremont rate center in CA, area code 909. It is part of the Los Angeles-Long Beach-Anaheim, CA Metropolitan Statistical Area.

Which company owns 909-344 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 909-344 safe to answer?

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