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: 425

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
551-425 A Ramsey NJ NWRKNJMDDSK  637C ONVOY, LLC - NJ 224   2025-10-04   
551-425 0 Ramsey NJ NWRKNJMDDSK  637C ONVOY, LLC - NJ 224   2025-10-04   
551-425 1 Ramsey NJ NWRKNJMDDSK  637C ONVOY, LLC - NJ 224   2026-02-23   
551-425 8 Ramsey NJ NWRKNJMDDSK  637C ONVOY, LLC - NJ 224   2026-06-25   
551-425 9 Ramsey NJ NWRKNJ0248Z  118F BANDWIDTH.COM CLEC, LLC - NJ 224   2026-07-13   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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