Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 551 [Rate centres in NPA 551] [Dial plan for NPA 551]

NXX: 438

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-438 A Union City NJ   637C ONVOY, LLC - NJ 224   2026-09-17   
551-438 0 Union City NJ   637C ONVOY, LLC - NJ 224   2026-09-17   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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