Local Calling Guide

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NPA: 571 [Rate centres in NPA 571] [Dial plan for NPA 571]

NXX: 491

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-491 A Dulles VA BTVLMD12CM9  5562 METROPCS, INC. 236      
571-491 0 Dulles VA   145J TERRA NOVA TELECOM INC. 236   2024-09-11   
571-491 1 Dulles VA   145J TERRA NOVA TELECOM INC. 236   2024-02-14   
571-491 2 Dulles VA   5562 METROPCS, INC. 236   2018-07-16   
571-491 3 Dulles VA   515J IP HORIZON LLC 236   2024-12-26   
571-491 4 Dulles VA   079F BANDWIDTH.COM CLEC, LLC - VA 236   2019-05-30   
571-491 5 Dulles VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2019-08-10   
571-491 6 Dulles VA   275G PEERLESS NETWORK OF VIRGINIA, LLC - VA 236   2019-07-11   
571-491 7 Dulles VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2019-05-10   
571-491 8 Dulles VA   8825 LEVEL 3 COMMUNICATIONS, LLC - VA 236   2019-04-12   
571-491 9 Dulles VA   5562 METROPCS, INC. 236   2017-11-17   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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