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: 433

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-433 A Hackensack NJ   700J WAVENATION, LLC 224   2026-01-31   
551-433 0 Hackensack NJ   700J WAVENATION, LLC 224   2026-01-31   
551-433 1 Hackensack NJ   637C ONVOY, LLC - NJ 224   2026-02-02   
551-433 8 Hackensack NJ   637C ONVOY, LLC - NJ 224   2026-03-15   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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