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: 920 [Rate centres in NPA 920] [Dial plan for NPA 920]

NXX: 578

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
920-578 A Markesan WI MILXWIJIGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356      
920-578 0 Markesan WI MILXWIJIGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2010-12-23   
920-578 1 Markesan WI   6529 T-MOBILE USA, INC. 356   2025-02-21   
920-578 5 Markesan WI MILWWI12XTX  624H ONVOY SPECTRUM, LLC 356   2021-06-26   
920-578 8 Markesan WI MILWWIAUDS1  225C ONVOY, LLC - WI 356   2021-07-02   
920-578 9 Markesan WI   6529 T-MOBILE USA, INC. 356   2025-02-21   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.