Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 556

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-556 A Laconia NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-556 0 Laconia NH MNCHNHNI9MD  5562 METROPCS, INC. 122   2003-06-04   
603-556 1 Laconia NH MNCHNHNI9MD  5562 METROPCS, INC. 122   2003-06-04   
603-556 2 Laconia NH MNCHNHNI9MD  5562 METROPCS, INC. 122   2003-06-04   
603-556 3 Laconia NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2021-08-02   
603-556 4 Laconia NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-556 5 Laconia NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2023-02-23   
603-556 6 Laconia NH   145J TERRA NOVA TELECOM INC. 122   2022-08-04   
603-556 7 Laconia NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-07-15   
603-556 8 Laconia NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-07-15   
603-556 9 Laconia NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122   2010-08-08   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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