Local Calling Guide

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NPA: 978 [Rate centres in NPA 978] [Dial plan for NPA 978]

NXX: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
978-303 A Westford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2025-04-11   
978-303 0 Westford MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
978-303 1 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-08-14   
978-303 2 Westford MA   829J PAETEC ITEL, LLC 128   2004-10-08   
978-303 4 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
978-303 5 Westford MA NRTNMAAACM4  5562 METROPCS, INC. 128   2005-06-24   
978-303 6 Westford MA MRBOMAFZDS0  7135 TC SYSTEMS, INC. 128   2002-12-21   
978-303 7 Westford MA CMBSMA01AMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2003-09-30   
978-303 8 Westford MA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128   2007-06-15   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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