Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 337 [Rate centres in NPA 337] [Dial plan for NPA 337]

NXX: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
337-310 A Lake Charles LA   7488 LEVEL 3 TELECOM OF LOUISIANA, LLC - LA 488      

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

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