Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 640

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-640 A Hudson CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-640 0 Hudson CO   073H TELNYX LLC 656   2019-04-29   
720-640 1 Hudson CO   073H TELNYX LLC 656   2020-01-29   
720-640 2 Hudson CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2019-03-21   
720-640 3 Hudson CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2019-09-27   
720-640 4 Hudson CO   026D ONVOY, LLC - CO 656   2019-10-26   
720-640 5 Hudson CO   278F PEERLESS NETWORK OF COLORADO, LLC - CO 656   2020-11-07   
720-640 6 Hudson CO   026D ONVOY, LLC - CO 656   2019-09-09   
720-640 7 Hudson CO   026D ONVOY, LLC - CO 656   2019-09-09   
720-640 8 Hudson CO   026D ONVOY, LLC - CO 656   2019-06-25   
720-640 9 Hudson CO   026D ONVOY, LLC - CO 656   2019-06-25   

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

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