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: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

<< 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 >>

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-328 4 Sykesville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-22   
443-328 5 Sykesville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2015-10-16   
443-328 6 Sykesville MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-01-26   
443-328 7 Sykesville MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-328 8 Sykesville MD   515J IP HORIZON LLC 238   2016-05-31   
443-328 9 Sykesville MD   515J IP HORIZON LLC 238   2015-03-21   
443-329 A Waterloo (Washington DC LATA) MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
443-329 1 Waterloo (Washington DC LATA) MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2026-09-24   
443-329 2 Waterloo (Washington DC LATA) MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-02-20   
443-329 3 Waterloo (Washington DC LATA) MD WASLDCRGDS0  281E YMAX COMMUNICATIONS CORP. - MD 236   2009-01-15   
443-329 4 Waterloo (Washington DC LATA) MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
443-329 5 Waterloo (Washington DC LATA) MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-06-20   
443-329 6 Waterloo (Washington DC LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-30   
443-329 7 Waterloo (Washington DC LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-30   
443-329 8 Waterloo (Washington DC LATA) MD WASHDC127MD  073H TELNYX LLC 236   2017-04-27   
443-329 9 Waterloo (Washington DC LATA) MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-06-20   
443-330 A Cockeysville MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-330 0 Cockeysville MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-330 1 Cockeysville MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-330 2 Cockeysville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-330 3 Cockeysville MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2005-03-10   
443-330 4 Cockeysville MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2004-09-05   
443-330 5 Cockeysville MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-10-22   
443-330 6 Cockeysville MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2011-04-13   
443-330 7 Cockeysville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2013-09-08   
443-330 8 Cockeysville MD MANRMDMNRS0  9212 VERIZON MARYLAND, INC. 238   2006-10-16   
443-330 9 Cockeysville MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-331 A Taneytown MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-331 0 Taneytown MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-331 1 Taneytown MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238      
443-331 2 Taneytown MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-03-03   
443-331 3 Taneytown MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-11-25   
443-331 4 Taneytown MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-21   
443-331 5 Taneytown MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-21   
443-331 7 Taneytown MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-331 8 Taneytown MD BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-07-17   
443-331 9 Taneytown MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-08   
443-332 A Crofton MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-332 0 Crofton MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-332 1 Crofton MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-12   
443-332 2 Crofton MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-08-30   
443-332 3 Crofton MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-03-03   
443-332 4 Crofton MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2002-07-12   
443-332 5 Crofton MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-08-30   
443-332 6 Crofton MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2006-03-28   
443-332 7 Crofton MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-332 8 Crofton MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-11-29   
443-332 9 Crofton MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-333 A Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-333 0 Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-02   

<< 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 >>

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.