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: 203

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
820-203 A Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740      
820-203 0 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 1 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 2 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 3 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 4 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 5 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-29   
820-203 6 Atascadero CA SNLOCA01X1Y  6010 NEW CINGULAR WIRELESS PCS, LLC 740   2021-05-11   
820-203 7 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-10   
820-203 8 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-10   
820-203 9 Atascadero CA SNLOCA01XYX  6529 T-MOBILE USA, INC. 740   2021-05-10   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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