Local Calling Guide

Area code/prefix search

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NPA: 712 [Rate centres in NPA 712] [Dial plan for NPA 712]

NXX: 566

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
712-566 A Underwood IA UNWDIACORS1  9631 QWEST CORPORATION 644      
712-566 0 Underwood IA   318J COMCAST IP PHONE, LLC 644   2005-02-20   
712-566 1 Underwood IA   508J CENTURYLINK COMMUNICATIONS, LLC 644   2015-01-22   
712-566 2 Underwood IA   9631 QWEST CORPORATION 644      
712-566 3 Underwood IA   9631 QWEST CORPORATION 644      
712-566 4 Underwood IA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 644   2014-01-31   
712-566 5 Underwood IA   985E BANDWIDTH.COM CLEC, LLC - IA 644   2011-10-09   
712-566 6 Underwood IA   221F ONVOY, LLC - IA 644   2013-04-04   
712-566 7 Underwood IA   221F ONVOY, LLC - IA 644   2008-09-04   
712-566 8 Underwood IA   774B WALNUT TELEPHONE COMPANY, INC. - IA 644   2006-12-30   
712-566 9 Underwood IA   9631 QWEST CORPORATION 644      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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