Local Calling Guide

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NPA: 617 [Rate centres in NPA 617] [Dial plan for NPA 617]

NXX: 668

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-668 A Watertown MA CATNMAAKPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128      
617-668 1 Watertown MA   892D ONVOY, LLC - MA 128   2020-06-21   
617-668 2 Watertown MA   7135 TC SYSTEMS, INC. 128   2020-02-13   
617-668 3 Watertown MA   7135 TC SYSTEMS, INC. 128   2010-06-03   
617-668 4 Watertown MA   7135 TC SYSTEMS, INC. 128   2015-09-14   
617-668 5 Watertown MA   7135 TC SYSTEMS, INC. 128   2016-02-15   
617-668 6 Watertown MA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128      
617-668 7 Watertown MA   7135 TC SYSTEMS, INC. 128   2019-11-21   
617-668 8 Watertown MA   7135 TC SYSTEMS, INC. 128   2019-11-21   
617-668 9 Watertown MA   145J TERRA NOVA TELECOM INC. 128   2022-05-05   

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

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