Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 323 [Rate centres in NPA 323] [Dial plan for NPA 323]

NXX: 742

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
323-742 A Montebello CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
323-742 0 Montebello CA   6529 T-MOBILE USA, INC. 730   2006-07-10   
323-742 1 Montebello CA   6529 T-MOBILE USA, INC. 730   2006-08-03   
323-742 2 Montebello CA   6529 T-MOBILE USA, INC. 730   2006-09-02   
323-742 3 Montebello CA   6529 T-MOBILE USA, INC. 730   2006-09-02   
323-742 4 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-19   
323-742 5 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-19   
323-742 6 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-19   
323-742 7 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-01   
323-742 8 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-01   
323-742 9 Montebello CA   899D METROPCS NETWORKS, LLC 730   2006-07-01   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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