Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 573 [Rate centres in NPA 573] [Dial plan for NPA 573]

NXX: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-240 A Center MO STLSMOPLDS4  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520      
573-240 0 Center MO   993E BANDWIDTH.COM CLEC, LLC - MO 520   2009-01-18   
573-240 1 Center MO   093F ONVOY, LLC - MO 520   2018-11-30   
573-240 2 Center MO   093F ONVOY, LLC - MO 520   2016-09-26   
573-240 3 Center MO   093F ONVOY, LLC - MO 520   2016-09-26   
573-240 4 Center MO   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520   2005-01-23   
573-240 5 Center MO   516C AT&T CORP. 520   2011-05-20   
573-240 6 Center MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2012-10-15   
573-240 7 Center MO   624H ONVOY SPECTRUM, LLC 520   2024-03-23   
573-240 8 Center MO   093F ONVOY, LLC - MO 520   2016-04-14   
573-240 9 Center MO   093F ONVOY, LLC - MO 520   2016-04-14   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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