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: 397

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-397 A Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348      
231-397 0 Manistee MI   515J IP HORIZON LLC 348   2021-12-31   
231-397 1 Manistee MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2022-07-09   
231-397 2 Manistee MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2022-08-24   
231-397 3 Manistee MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-04-01   
231-397 4 Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2021-12-18   
231-397 5 Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2021-12-18   
231-397 6 Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2021-12-18   
231-397 7 Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2021-12-18   
231-397 8 Manistee MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2021-12-18   
231-397 9 Manistee MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2022-09-06   

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

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