Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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 DNVRCO26XJY  824J OPENTACT INC. 656   2026-05-10   
983-587 0 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2026-05-11   
983-587 1 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2026-06-08   
983-587 2 Denver CO DNVRCO2669Z  490J BOOST SUBSCRIBERCO L.L.C. 656   2026-07-01   
983-587 3 Denver CO DNVRCO2669Z  490J BOOST SUBSCRIBERCO L.L.C. 656   2026-08-17   
983-587 4 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2026-05-21   
983-587 5 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2026-05-21   
983-587 6 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2026-05-21   
983-587 7 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2026-05-21   
983-587 8 Denver CO DNVRCO26XJY  824J OPENTACT INC. 656   2026-05-10   
983-587 9 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2026-06-22   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.