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: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-304 A Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-304 0 Enfield NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-07   
603-304 2 Enfield NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2015-08-20   
603-304 3 Enfield NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2025-05-03   
603-304 4 Enfield NH   5562 METROPCS, INC. 122   2025-05-31   
603-304 5 Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-304 6 Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-304 7 Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-304 8 Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-304 9 Enfield NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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