Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 820 [Rate centres in NPA 820] [Dial plan for NPA 820]

NXX: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
820-237 A Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2025-02-10   
820-237 7 Atascadero CA   6529 T-MOBILE USA, INC. 740   2025-02-23   
820-237 8 Atascadero CA   6529 T-MOBILE USA, INC. 740   2025-02-23   
820-237 9 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2025-02-10   

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

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