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: 501 [Rate centres in NPA 501] [Dial plan for NPA 501]

NXX: 991

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
501-991 A Crystal Springs AR CRSPARMARS2  9533 SOUTHWESTERN BELL 528      
501-991 0 Crystal Springs AR LTRKARFRXLY  348F ONVOY, LLC - AR 528   2019-01-12   
501-991 1 Crystal Springs AR CRSPARMARS2  9533 SOUTHWESTERN BELL 528      
501-991 2 Crystal Springs AR LTRKARFRXWY  516C AT&T CORP. 528   2011-04-25   
501-991 3 Crystal Springs AR CRSPARMARS2  9533 SOUTHWESTERN BELL 528      
501-991 4 Crystal Springs AR LTRKARFRXKY  196F BANDWIDTH.COM CLEC, LLC - AR 528   2015-02-15   
501-991 5 Crystal Springs AR LTRKARFRXLY  348F ONVOY, LLC - AR 528   2017-03-27   
501-991 6 Crystal Springs AR LTRKARWTBMD  5179 LEVEL 3 COMMUNICATIONS, LLC - AR 528   2017-09-11   
501-991 7 Crystal Springs AR RLVLARFI2MD  508J CENTURYLINK COMMUNICATIONS, LLC 528   2015-01-13   
501-991 8 Crystal Springs AR LTRKARFRXLY  348F ONVOY, LLC - AR 528   2019-01-12   
501-991 9 Crystal Springs AR LTRKARZO2MD  073H TELNYX LLC 528   2018-11-26   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.