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 4 Hackensack NJ   490J BOOST SUBSCRIBERCO L.L.C. 224   2026-01-26   
551-423 5 Hackensack NJ   321J HD CARRIER LLC 224   2025-12-11   
551-423 6 Hackensack NJ   321J HD CARRIER LLC 224   2025-12-11   
551-423 7 Hackensack NJ   321J HD CARRIER LLC 224   2025-12-11   
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: Tue, 16 Jun 2026 00:09:45 UTC

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