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: 991

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-991 A Mexico MO STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520   2024-05-30   
573-991 0 Mexico MO STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520   2024-05-30   
573-991 1 Mexico MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-06-01   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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