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: 850

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-850 A Denver CO DNVRCO26XYX  598J FIVE9, INC. 656      
720-850 0 Denver CO   598J FIVE9, INC. 656   2021-07-11   
720-850 1 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 2 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 3 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 4 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 5 Denver CO   026D ONVOY, LLC - CO 656   2021-07-12   
720-850 6 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 7 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   
720-850 8 Denver CO   026D ONVOY, LLC - CO 656   2021-07-12   
720-850 9 Denver CO   6529 T-MOBILE USA, INC. 656   2021-08-29   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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