Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 840 [Rate centres in NPA 840] [Dial plan for NPA 840]

NXX: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
840-278 A Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-08-15   
840-278 0 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 1 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 2 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 3 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 4 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 5 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 6 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-09-14   
840-278 7 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-08-15   
840-278 8 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-08-15   
840-278 9 Arrowhead CA   6529 T-MOBILE USA, INC. 730   2025-08-15   

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

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