Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 508

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-508 A Onekama MI TRCYMIMNLMD  392F KALEVA TELEPHONE COMPANY - MI 348      
231-508 0 Onekama MI TRCYMIMNLMD  392F KALEVA TELEPHONE COMPANY - MI 348   2008-07-25   
231-508 1 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2015-08-02   
231-508 2 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-508 3 Onekama MI GDRQMIBODS0  7157 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 348   2016-10-07   
231-508 4 Onekama MI TRCYMIMNWMD  508J CENTURYLINK COMMUNICATIONS, LLC 348   2017-10-04   
231-508 5 Onekama MI GDRPMIBL15Z  516C AT&T CORP. 348   2011-08-23   
231-508 6 Onekama MI GDRPMIBL06Z  770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2016-10-10   
231-508 7 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-04-15   
231-508 8 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2013-03-18   
231-508 9 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-04-15   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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