Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 520 [Rate centres in NPA 520] [Dial plan for NPA 520]

NXX: 735

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-735 A Sierra Vista AZ TCSNAZMAXKX  7217 TELEPORT COMMUNICATIONS AMERICA, LLC - AZ 668   2024-05-27   
520-735 0 Sierra Vista AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 668   2025-08-22   
520-735 1 Sierra Vista AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 668   2025-10-31   
520-735 6 Sierra Vista AZ TCSNAZMAXKX  7217 TELEPORT COMMUNICATIONS AMERICA, LLC - AZ 668   2025-09-16   
520-735 8 Sierra Vista AZ   6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 668   2025-12-18   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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