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: 785

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-785 A Tucson AZ   907K ALLO COMMUNICATIONS LLC 668   2025-12-19   
520-785 5 Tucson AZ   907K ALLO COMMUNICATIONS LLC 668   2025-12-19   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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