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: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 438

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-438 A Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 2 Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 3 Phoenix AZ   490J BOOST SUBSCRIBERCO L.L.C. 666   2026-09-30   
623-438 8 Phoenix AZ   883K AHOI LLC 666   2026-09-28   
623-438 9 Phoenix AZ   883K AHOI LLC 666   2026-09-28   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.