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: 475 [Rate centres in NPA 475] [Dial plan for NPA 475]

NXX: 392

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-392 A New Haven CT   639C ONVOY, LLC - CT 920   2025-06-07   
475-392 0 New Haven CT   639C ONVOY, LLC - CT 920   2025-06-07   
475-392 1 New Haven CT   490J BOOST SUBSCRIBERCO L.L.C. 920   2025-09-04   
475-392 2 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2025-10-07   
475-392 3 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2025-10-07   
475-392 4 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2025-10-07   
475-392 8 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2026-02-16   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.