Local Calling Guide

Area code/prefix search

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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-531 A Muskegon MI GDRPMIBL31Z  5562 METROPCS, INC. 348      
231-531 0 Muskegon MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2019-09-19   
231-531 1 Muskegon MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2019-10-22   
231-531 2 Muskegon MI WYNGMIKAGT2  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2019-10-22   
231-531 3 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2020-07-06   
231-531 4 Muskegon MI GDRPMIBL31Z  5562 METROPCS, INC. 348   2020-06-26   
231-531 5 Muskegon MI GDRPMIBL31Z  5562 METROPCS, INC. 348   2020-06-26   
231-531 6 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2020-07-06   
231-531 7 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2020-07-06   
231-531 8 Muskegon MI GDRPMIBL40Z  318J COMCAST IP PHONE, LLC 348   2020-11-12   
231-531 9 Muskegon MI GDRPMIBL31Z  5562 METROPCS, INC. 348   2019-05-31   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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