Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 661 [Rate centres in NPA 661] [Dial plan for NPA 661]

NXX: 606

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-606 A Arvin CA BKFDCA01X2X  6529 T-MOBILE USA, INC. 734      
661-606 0 Arvin CA   6529 T-MOBILE USA, INC. 734   2020-08-02   
661-606 1 Arvin CA   6529 T-MOBILE USA, INC. 734   2014-08-14   
661-606 2 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-06-08   
661-606 3 Arvin CA   7128 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CA 734   2005-04-28   
661-606 4 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-06-08   
661-606 5 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-06-08   
661-606 6 Arvin CA   7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 734   2012-11-19   
661-606 7 Arvin CA   9262 UTILITY TELECOM GROUP, LLC - CA 734   2013-04-11   
661-606 8 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-06-08   
661-606 9 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-06-08   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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