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: 279 [Rate centres in NPA 279] [Dial plan for NPA 279]

NXX: 321

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
279-321 A Folsom CA SCRMCA01XSY  649C ONVOY, LLC - CA 726      
279-321 0 Folsom CA   649C ONVOY, LLC - CA 726   2018-09-22   
279-321 1 Folsom CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 726   2019-06-15   
279-321 2 Folsom CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 726   2019-07-30   
279-321 3 Folsom CA   6529 T-MOBILE USA, INC. 726   2019-08-13   
279-321 4 Folsom CA   649C ONVOY, LLC - CA 726   2019-02-25   
279-321 5 Folsom CA   515J IP HORIZON LLC 726   2018-05-11   
279-321 6 Folsom CA   6010 NEW CINGULAR WIRELESS PCS, LLC 726   2018-11-03   
279-321 7 Folsom CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 726   2018-10-21   
279-321 8 Folsom CA   649C ONVOY, LLC - CA 726   2018-09-22   
279-321 9 Folsom CA   6529 T-MOBILE USA, INC. 726   2018-07-08   

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

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.