Local Calling Guide

Area code/prefix search

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

NXX: 312

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-312 A Monterey CA SLNSCA01XSY  388E CEBRIDGE TELECOM CA, LLC DBA SUDDENLINK COMMS - CA 736   2024-05-26   
831-312 0 Monterey CA SLNSCA01XEY  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 736   2024-05-27   
831-312 1 Monterey CA SLNSCA01X9Y  649C ONVOY, LLC - CA 736   2024-06-29   
831-312 2 Monterey CA   649C ONVOY, LLC - CA 736   2025-05-10   
831-312 4 Monterey CA SLNSCA01X9Y  649C ONVOY, LLC - CA 736   2024-07-15   
831-312 5 Monterey CA SLNSCA01XSY  388E CEBRIDGE TELECOM CA, LLC DBA SUDDENLINK COMMS - CA 736   2024-05-26   
831-312 6 Monterey CA SLNSCA01X8Y  6529 T-MOBILE USA, INC. 736   2024-09-15   
831-312 8 Monterey CA SLNSCA01XEY  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 736   2024-07-20   
831-312 9 Monterey CA SLNSCA01XEY  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 736   2024-08-20   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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