Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

<< 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 >>

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-371 7 Peterborough NH   145J TERRA NOVA TELECOM INC. 122   2021-05-27   
603-371 8 Peterborough NH   829J PAETEC ITEL, LLC 122   2006-05-03   
603-371 9 Peterborough NH   829J PAETEC ITEL, LLC 122   2000-05-24   
603-372 A Claremont NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-372 0 Claremont NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-372 1 Claremont NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-372 2 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2007-05-03   
603-372 4 Claremont NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-372 5 Claremont NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-372 6 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2008-11-03   
603-372 7 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2008-05-02   
603-372 9 Claremont NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-373 A Portsmouth NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-373 0 Portsmouth NH   318J COMCAST IP PHONE, LLC 122   2001-01-01   
603-373 1 Portsmouth NH   829J PAETEC ITEL, LLC 122   2004-11-01   
603-373 2 Portsmouth NH   7421 AT&T - LOCAL 122   2001-07-01   
603-373 3 Portsmouth NH   145J TERRA NOVA TELECOM INC. 122   2021-05-27   
603-373 4 Portsmouth NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2004-04-18   
603-373 5 Portsmouth NH   4053 CONVERSENT COMMUNICATIONS OF NEW HAMPSHIRE, LLC 122      
603-373 6 Portsmouth NH   829J PAETEC ITEL, LLC 122      
603-373 7 Portsmouth NH   829J PAETEC ITEL, LLC 122   2005-08-05   
603-373 8 Portsmouth NH   318J COMCAST IP PHONE, LLC 122   2003-02-04   
603-373 9 Portsmouth NH   829J PAETEC ITEL, LLC 122   2000-07-03   
603-374 A Bartlett NH BRTLNHGERS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-374 0 Bartlett NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-374 1 Bartlett NH   145J TERRA NOVA TELECOM INC. 122   2024-08-07   
603-374 2 Bartlett NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-374 3 Bartlett NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2009-01-05   
603-374 4 Bartlett NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2014-09-10   
603-374 5 Bartlett NH   793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   
603-374 6 Bartlett NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-374 7 Bartlett NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2004-09-03   
603-374 8 Bartlett NH   829J PAETEC ITEL, LLC 122   2007-12-06   
603-374 9 Bartlett NH   145J TERRA NOVA TELECOM INC. 122   2023-01-04   
603-375 A Ashland NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122      
603-375 0 Ashland NH   073H TELNYX LLC 122   2024-07-22   
603-375 3 Ashland NH   637E ONVOY, LLC - NH 122   2025-02-02   
603-375 4 Ashland NH   793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   
603-376 A Dover NH MNCHNHCO29Z  9748 AMERICAN MESSAGING SERVICES, LLC 122      
603-377 A Merrimack NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-377 0 Merrimack NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-377 1 Merrimack NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2016-11-19   
603-377 2 Merrimack NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-08-07   
603-377 3 Merrimack NH   637E ONVOY, LLC - NH 122   2022-01-15   
603-377 4 Merrimack NH   637E ONVOY, LLC - NH 122   2022-08-28   
603-377 5 Merrimack NH   073H TELNYX LLC 122   2023-08-26   
603-377 6 Merrimack NH   5562 METROPCS, INC. 122      
603-377 7 Merrimack NH   318J COMCAST IP PHONE, LLC 122   2012-04-30   
603-377 8 Merrimack NH   637E ONVOY, LLC - NH 122   2021-11-13   
603-377 9 Merrimack NH   145J TERRA NOVA TELECOM INC. 122   2021-05-27   

<< 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 >>

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

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.