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: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-503 A Middletown MO STLSMOPLDS4  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520      
573-503 0 Middletown MO STLSMOWQ8MD  073H TELNYX LLC 520   2020-08-02   
573-503 1 Middletown MO STLSMO05RMD  993E BANDWIDTH.COM CLEC, LLC - MO 520   2021-09-18   
573-503 3 Middletown MO STLSMO05XPX  506J TWILIO INTERNATIONAL, INC. 520   2021-06-06   
573-503 4 Middletown MO STLSMOPLDS4  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 520   2006-06-30   
573-503 8 Middletown MO   624H ONVOY SPECTRUM, LLC 520   2024-03-23   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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