Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 983 [Rate centres in NPA 983] [Dial plan for NPA 983]

NXX: 999

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-999 A Denver CO DNVRCO26XBY  557H WIDE VOICE, LLC - CO 656      
983-999 0 Denver CO   026D ONVOY, LLC - CO 656   2023-10-09   
983-999 1 Denver CO   321J HD CARRIER LLC 656   2023-10-08   
983-999 2 Denver CO   026D ONVOY, LLC - CO 656   2023-10-09   
983-999 3 Denver CO   321J HD CARRIER LLC 656   2023-10-08   
983-999 4 Denver CO   318J COMCAST IP PHONE, LLC 656   2023-10-21   
983-999 5 Denver CO   318J COMCAST IP PHONE, LLC 656   2023-10-21   
983-999 6 Denver CO   318J COMCAST IP PHONE, LLC 656   2023-10-21   
983-999 7 Denver CO   732J NUSO, LLC 656   2024-01-30   
983-999 8 Denver CO   026D ONVOY, LLC - CO 656   2023-10-09   
983-999 9 Denver CO   557H WIDE VOICE, LLC - CO 656   2023-10-08   

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

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