Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 320 [Rate centres in NPA 320] [Dial plan for NPA 320]

NXX: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
320-400 A Olivia MN STCDMNTOXQX  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 626      
320-400 0 Olivia MN   184D ONVOY, LLC - MN 626   2012-12-17   
320-400 1 Olivia MN   184D ONVOY, LLC - MN 626   2012-12-17   
320-400 2 Olivia MN   184D ONVOY, LLC - MN 626   2013-04-22   
320-400 3 Olivia MN   980E BANDWIDTH.COM CLEC, LLC - MN 626   2015-06-18   
320-400 4 Olivia MN   965H FRACTEL, LLC 626   2020-02-06   
320-400 5 Olivia MN   4156 TEKSTAR COMMUNICATIONS, INC. 626   2023-06-16   
320-400 6 Olivia MN   8405 TELEPORT COMMUNICATIONS AMERICA, LLC - MN 626   2022-06-06   
320-400 7 Olivia MN   184D ONVOY, LLC - MN 626   2011-12-09   
320-400 8 Olivia MN   145J TERRA NOVA TELECOM INC. 626   2024-02-14   
320-400 9 Olivia MN   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 626   2011-01-10   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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