Local Calling Guide

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NPA: 831 [Rate centres in NPA 831] [Dial plan for NPA 831]

NXX: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-307 A Castroville CA SLNSCA01XXX  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736      
831-307 0 Castroville CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736      
831-307 1 Castroville CA   6010 NEW CINGULAR WIRELESS PCS, LLC 736   2025-01-19   
831-307 2 Castroville CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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