Local Calling Guide

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NPA: 641 [Rate centres in NPA 641] [Dial plan for NPA 641]

NXX: 243

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-243 A Mason City IA DESMIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 632      
641-243 0 Mason City IA DESMIAITX6X  6529 T-MOBILE USA, INC. 632   2012-05-25   
641-243 1 Mason City IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2012-12-14   
641-243 2 Mason City IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2012-12-14   
641-243 3 Mason City IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2012-12-14   
641-243 4 Mason City IA DESMIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 632   2009-12-24   
641-243 5 Mason City IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2012-12-14   
641-243 6 Mason City IA DESMIADTX5X  8344 TELEPORT COMMUNICATIONS AMERICA, LLC - IA 632   2012-03-12   
641-243 7 Mason City IA MSCYIA601MD  6103 WINNEBAGO COOPERATIVE TELEPHONE ASSOCIATION - IA 632   2011-02-25   
641-243 8 Mason City IA DESMIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 632   2013-06-22   
641-243 9 Mason City IA DESMIAITX6X  6529 T-MOBILE USA, INC. 632   2011-05-19   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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