Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Colby, WI

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
715-721 6 GNBYWI01XMX  6508 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WI 350   2015-07-17   
715-721 7 CRVTWIXA4MD  508J CENTURYLINK COMMUNICATIONS, LLC 350   2014-11-26   
715-721 8 STPTWI01HMD  7216 TELEPORT COMMUNICATIONS AMERICA, LLC WI 350   2018-11-09   
715-721 9 MNSHWIDQCM0  6274 UNITED STATES CELLULAR - WI 350   2019-06-24   

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Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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