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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-421 A Union City NJ   4948 CABLEVISION LIGHTPATH, INC. - NJ 224   2025-05-30   
551-421 0 Union City NJ   637C ONVOY, LLC - NJ 224   2025-06-02   
551-421 1 Union City NJ   637C ONVOY, LLC - NJ 224   2025-06-02   
551-421 2 Union City NJ   637C ONVOY, LLC - NJ 224   2025-06-02   
551-421 3 Union City NJ   4948 CABLEVISION LIGHTPATH, INC. - NJ 224   2025-05-30   
551-421 4 Union City NJ   4948 CABLEVISION LIGHTPATH, INC. - NJ 224   2025-05-30   
551-421 9 Union City NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 224   2025-11-21   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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