Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 616

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-616 A Keenesburg CO DNVRCOSOFMD  624H ONVOY SPECTRUM, LLC 656      
303-616 0 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 1 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 2 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 3 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 4 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 5 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 6 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 7 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 8 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   
303-616 9 Keenesburg CO   624H ONVOY SPECTRUM, LLC 656   2022-01-17   

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

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