Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 837 [Rate centres in NPA 837] [Dial plan for NPA 837]

NXX: 444

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
837-444 A Chico CA   114J EXIANT COMMUNICATIONS LLC 724   2026-10-24   
837-444 4 Chico CA   114J EXIANT COMMUNICATIONS LLC 724   2026-10-24   

Last updated: Tue, 29 Sep 2026 03:00:13 UTC

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