Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 442 [Rate centres in NPA 442] [Dial plan for NPA 442]

NXX: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
442-503 A San Marcos CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2026-10-17   
442-503 0 San Marcos CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2026-10-17   

Last updated: Tue, 29 Sep 2026 03:00:13 UTC

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