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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-423 A Hackensack NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 224   2025-07-04   
551-423 0 Hackensack NJ   637C ONVOY, LLC - NJ 224   2025-10-26   
551-423 1 Hackensack NJ   637C ONVOY, LLC - NJ 224   2025-10-26   
551-423 2 Hackensack NJ   490J DISH WIRELESS, LLC 224   2025-09-29   
551-423 3 Hackensack NJ   490J DISH WIRELESS, LLC 224   2025-11-24   
551-423 4 Hackensack NJ   490J DISH WIRELESS, LLC 224   2026-01-26   
551-423 8 Hackensack NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 224   2025-07-04   
551-423 9 Hackensack NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 224   2025-07-04   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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