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: 443

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-443 A Chula Vista CA   6529 T-MOBILE USA, INC. 732   2025-12-18   
858-443 0 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2026-01-23   
858-443 1 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2026-01-23   
858-443 2 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2026-01-23   
858-443 6 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2025-12-18   
858-443 7 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2025-12-18   
858-443 8 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2025-12-18   
858-443 9 Chula Vista CA   6529 T-MOBILE USA, INC. 732   2025-12-18   

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

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