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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-423 A Lancaster CA LNCSCAXFDS0  2319 FRONTIER CALIFORNIA INC. 730      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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