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: 310 [Rate centres in NPA 310] [Dial plan for NPA 310]

NXX: 855

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-855 A Beverly Hills CA LSANCA08DS0  9740 PACIFIC BELL 730      
310-855 0 Beverly Hills CA   9740 PACIFIC BELL 730      
310-855 1 Beverly Hills CA   9740 PACIFIC BELL 730      
310-855 2 Beverly Hills CA   6529 T-MOBILE USA, INC. 730   2007-07-24   
310-855 3 Beverly Hills CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2005-09-09   
310-855 4 Beverly Hills CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2006-01-14   
310-855 5 Beverly Hills CA   9262 UTILITY TELECOM GROUP, LLC - CA 730   2005-06-26   
310-855 6 Beverly Hills CA   9740 PACIFIC BELL 730      
310-855 7 Beverly Hills CA   9740 PACIFIC BELL 730      
310-855 8 Beverly Hills CA   9740 PACIFIC BELL 730      
310-855 9 Beverly Hills CA   9740 PACIFIC BELL 730      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.