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: 266

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-266 A Oak Ridge MO OKRGMOAMRSN  9533 SOUTHWESTERN BELL 520      
573-266 0 Oak Ridge MO   515J IP HORIZON LLC 520   2023-12-30   
573-266 1 Oak Ridge MO   9533 SOUTHWESTERN BELL 520      
573-266 2 Oak Ridge MO   093F ONVOY, LLC - MO 520   2016-09-28   
573-266 3 Oak Ridge MO   9533 SOUTHWESTERN BELL 520      
573-266 4 Oak Ridge MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2022-01-29   
573-266 5 Oak Ridge MO   516C AT&T CORP. 520   2011-05-20   
573-266 6 Oak Ridge MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2013-05-06   
573-266 7 Oak Ridge MO   515J IP HORIZON LLC 520   2023-12-30   
573-266 8 Oak Ridge MO   073H TELNYX LLC 520   2019-09-30   
573-266 9 Oak Ridge MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2013-05-06   

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

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