Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 978 [Rate centres in NPA 978] [Dial plan for NPA 978]

NXX: 923

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
978-923 A Westford MA   892D ONVOY, LLC - MA 128   2025-04-03   
978-923 1 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2023-11-03   
978-923 5 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2019-07-01   
978-923 6 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
978-923 8 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2005-08-13   
978-923 9 Westford MA CMBSMA01AMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2020-05-31   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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