Local Calling Guide

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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-304 A Watertown MA CMBRMA01DS5  7135 TC SYSTEMS, INC. 128      
857-304 0 Watertown MA   892D ONVOY, LLC - MA 128   2014-09-14   
857-304 1 Watertown MA   515J IP HORIZON LLC 128   2015-03-26   
857-304 2 Watertown MA   829J PAETEC ITEL, LLC 128   2015-05-04   
857-304 3 Watertown MA   7135 TC SYSTEMS, INC. 128   2013-05-10   
857-304 4 Watertown MA   318J COMCAST IP PHONE, LLC 128   2014-09-19   
857-304 5 Watertown MA   7135 TC SYSTEMS, INC. 128   2014-10-27   
857-304 6 Watertown MA   7135 TC SYSTEMS, INC. 128   2015-06-22   
857-304 7 Watertown MA   508J CENTURYLINK COMMUNICATIONS, LLC 128   2014-04-24   
857-304 8 Watertown MA   7135 TC SYSTEMS, INC. 128   2015-04-20   
857-304 9 Watertown MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2015-06-07   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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