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: 321

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-321 A Park Ridge NJ NWRKNJMDDSK  637C ONVOY, LLC - NJ 224      
551-321 0 Park Ridge NJ   073H TELNYX LLC 224   2022-01-03   
551-321 1 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2020-09-19   
551-321 2 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2020-09-19   
551-321 3 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2025-03-09   
551-321 4 Park Ridge NJ   624H ONVOY SPECTRUM, LLC 224   2021-05-07   
551-321 5 Park Ridge NJ   624H ONVOY SPECTRUM, LLC 224   2022-04-17   
551-321 6 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2021-03-12   
551-321 7 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2021-03-12   
551-321 8 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2021-07-15   
551-321 9 Park Ridge NJ   637C ONVOY, LLC - NJ 224   2021-07-15   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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