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: 573 [Rate centres in NPA 573] [Dial plan for NPA 573]

NXX: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-237 A New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 1 New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 2 New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 3 New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 4 New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 5 New Haven MO NWHNMOXARS2  1882 FIDELITY TELEPHONE, LLC 520      
573-237 7 New Haven MO   145J TERRA NOVA TELECOM INC. 520   2025-07-12   
573-237 8 New Haven MO STLSMOGZHMD  516J TON80 COMMUNICATIONS, LLC 520   2022-02-22   

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

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.