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: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-303 A Tucson AZ   630E ONVOY, LLC - AZ 668   2025-03-09   
520-303 0 Tucson AZ   630E ONVOY, LLC - AZ 668   2008-02-23   
520-303 1 Tucson AZ   630E ONVOY, LLC - AZ 668   2008-02-23   
520-303 2 Tucson AZ TCSMAZCH1MD  6010 NEW CINGULAR WIRELESS PCS, LLC 668   2025-01-19   
520-303 3 Tucson AZ   630E ONVOY, LLC - AZ 668   2008-06-01   
520-303 4 Tucson AZ   630E ONVOY, LLC - AZ 668   2008-06-01   
520-303 5 Tucson AZ TCSMAZCH1MD  6010 NEW CINGULAR WIRELESS PCS, LLC 668   2024-12-03   
520-303 6 Tucson AZ TCSMAZCH1MD  6010 NEW CINGULAR WIRELESS PCS, LLC 668   2024-12-03   
520-303 7 Tucson AZ   630E ONVOY, LLC - AZ 668   2008-06-01   
520-303 8 Tucson AZ TCSMAZOI3MD  6529 T-MOBILE USA, INC. 668   2008-07-07   
520-303 9 Tucson AZ TCSNAZMAXHX  630E ONVOY, LLC - AZ 668   2008-06-01   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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