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: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
337-503 A Sulphur LA LFYTLAMAXRZ  829J PAETEC ITEL, LLC 488   2024-12-11   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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