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: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 661

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-661 A Waterloo MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-661 0 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-661 1 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-661 2 Waterloo MD   515J IP HORIZON LLC 238   2017-07-07   
443-661 3 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-661 4 Waterloo MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-10-06   
443-661 5 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-661 7 Waterloo MD BLTMMDCHXVX  321J HD CARRIER LLC 238   2020-05-02   
443-661 8 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-661 9 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-09-25   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

Sponsored by: BeeVox - Whitelabel Reseller Platform

Like this site? We accept donations via PayPal.