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: 816 [Rate centres in NPA 816] [Dial plan for NPA 816]

NXX: 851

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
816-851 A San Antonio MO KSCYMO09QMD  516C AT&T CORP. 524      
816-851 0 San Antonio MO KSCYMO55XYY  624H ONVOY SPECTRUM, LLC 524   2025-01-12   
816-851 7 San Antonio MO KSCYMO09QMD  516C AT&T CORP. 524   2023-10-09   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.