Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 530 [Rate centres in NPA 530] [Dial plan for NPA 530]

NXX: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
530-231 A Davis CA WSCRCAKE1MD  6529 T-MOBILE USA, INC. 726      
530-231 0 Davis CA   6529 T-MOBILE USA, INC. 726      
530-231 1 Davis CA   649C ONVOY, LLC - CA 726   2021-07-18   
530-231 2 Davis CA   6529 T-MOBILE USA, INC. 726      
530-231 3 Davis CA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 726   2006-03-10   
530-231 4 Davis CA   981E BANDWIDTH.COM CLEC, LLC - CA 726      
530-231 5 Davis CA   318J COMCAST IP PHONE, LLC 726   2006-09-30   
530-231 6 Davis CA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 726   2006-11-19   
530-231 7 Davis CA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 726   2008-11-09   
530-231 8 Davis CA   624H ONVOY SPECTRUM, LLC 726   2021-07-23   
530-231 9 Davis CA   649C ONVOY, LLC - CA 726   2021-07-18   

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

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