Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 610 [Rate centres in NPA 610] [Dial plan for NPA 610]

NXX: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
610-421 A Emmaus PA NATNPAAGGT0  7615 RCN TELECOM SERVICES OF PENNSYLVANIA, INC. 228      
610-421 0 Emmaus PA   547E ONVOY, LLC - PA 228   2016-04-04   
610-421 1 Emmaus PA   547E ONVOY, LLC - PA 228   2015-11-27   
610-421 2 Emmaus PA   551G NUSO, LLC 228   2016-09-24   
610-421 3 Emmaus PA   551G NUSO, LLC 228   2016-09-24   
610-421 4 Emmaus PA   4007 LEVEL 3 COMMUNICATIONS, LLC - PA 228   2005-09-10   
610-421 5 Emmaus PA   508J CENTURYLINK COMMUNICATIONS, LLC 228   2017-11-23   
610-421 6 Emmaus PA   7615 RCN TELECOM SERVICES OF PENNSYLVANIA, INC. 228      
610-421 7 Emmaus PA   7615 RCN TELECOM SERVICES OF PENNSYLVANIA, INC. 228      
610-421 8 Emmaus PA   7615 RCN TELECOM SERVICES OF PENNSYLVANIA, INC. 228      
610-421 9 Emmaus PA   547E ONVOY, LLC - PA 228   2016-04-04   

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

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