Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 858 [Rate centres in NPA 858] [Dial plan for NPA 858]

NXX: 323

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-323 A Chula Vista CA SNDACAGLDS2  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732      
858-323 0 Chula Vista CA   939H COMMIO, LLC 732   2021-09-24   
858-323 1 Chula Vista CA   939H COMMIO, LLC 732   2021-09-24   
858-323 2 Chula Vista CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2021-09-23   
858-323 3 Chula Vista CA   939H COMMIO, LLC 732   2021-09-24   
858-323 4 Chula Vista CA   939H COMMIO, LLC 732   2021-09-24   
858-323 5 Chula Vista CA   939H COMMIO, LLC 732   2021-09-24   
858-323 6 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2021-09-24   
858-323 7 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2021-09-24   
858-323 8 Chula Vista CA   624H ONVOY SPECTRUM, LLC 732   2021-11-12   
858-323 9 Chula Vista CA   624H ONVOY SPECTRUM, LLC 732   2021-11-12   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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