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: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-399 A Frankfort MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348      
231-399 0 Frankfort MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348      
231-399 1 Frankfort MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      
231-399 2 Frankfort MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348      
231-399 3 Frankfort MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-399 4 Frankfort MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-399 5 Frankfort MI GDRPMIBL15Z  516C AT&T CORP. 348      
231-399 6 Frankfort MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348      
231-399 7 Frankfort MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348      
231-399 8 Frankfort MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-399 9 Frankfort MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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