Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 318 [Rate centres in NPA 318] [Dial plan for NPA 318]

NXX: 921

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
318-921 A Shreveport LA   478J NUSO, LLC 486   2025-03-20   
318-921 1 Shreveport LA   478J NUSO, LLC 486   2025-03-20   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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