Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 508 [Rate centres in NPA 508] [Dial plan for NPA 508]

NXX: 603

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-603 A Upton MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-603 0 Upton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2006-09-01   
508-603 1 Upton MA   792K CHARTER IP ENABLED SERVICES, LLC 128   2005-01-01   
508-603 2 Upton MA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128   2018-02-27   
508-603 4 Upton MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2024-02-20   
508-603 5 Upton MA   829J PAETEC ITEL, LLC 128   2008-12-17   
508-603 6 Upton MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2015-07-13   
508-603 7 Upton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2004-09-05   
508-603 8 Upton MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2011-06-27   
508-603 9 Upton MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2008-12-06   

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

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