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: 587

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-587 A Denver CO   824J OPENTACT INC. 656   2026-05-10   
983-587 0 Denver CO   026D ONVOY, LLC - CO 656   2026-05-11   
983-587 1 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2026-06-08   
983-587 2 Denver CO   490J BOOST SUBSCRIBERCO L.L.C. 656   2026-07-01   
983-587 3 Denver CO   490J BOOST SUBSCRIBERCO L.L.C. 656   2026-08-17   
983-587 4 Denver CO   026D ONVOY, LLC - CO 656   2026-05-21   
983-587 5 Denver CO   026D ONVOY, LLC - CO 656   2026-05-21   
983-587 6 Denver CO   026D ONVOY, LLC - CO 656   2026-05-21   
983-587 7 Denver CO   026D ONVOY, LLC - CO 656   2026-05-21   
983-587 8 Denver CO   824J OPENTACT INC. 656   2026-05-10   
983-587 9 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2026-06-22   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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