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: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-678 A Denver CO DNVRCOMAY0X  425J CSC WIRELESS, LLC 656      
720-678 0 Denver CO   809C INTRADO COMMUNICATIONS, LLC 656   2019-11-24   
720-678 1 Denver CO   809C INTRADO COMMUNICATIONS, LLC 656   2019-11-24   
720-678 2 Denver CO   425J CSC WIRELESS, LLC 656   2019-11-23   
720-678 3 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-678 4 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-678 5 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-678 6 Denver CO   5562 METROPCS, INC. 656   2020-07-22   
720-678 7 Denver CO   5562 METROPCS, INC. 656   2020-07-22   
720-678 8 Denver CO   809C INTRADO COMMUNICATIONS, LLC 656   2019-11-24   
720-678 9 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2020-07-29   

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

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