Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 319 [Rate centres in NPA 319] [Dial plan for NPA 319]

NXX: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-503 A Cedar Rapids IA   478J NUSO, LLC 635   2025-04-24   
319-503 0 Cedar Rapids IA   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 635   2025-09-05   
319-503 1 Cedar Rapids IA   478J NUSO, LLC 635   2025-04-24   
319-503 2 Cedar Rapids IA   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 635   2025-12-26   
319-503 3 Cedar Rapids IA   490J BOOST SUBSCRIBERCO L.L.C. 635   2026-04-30   
319-503 4 Cedar Rapids IA   6529 T-MOBILE USA, INC. 635   2026-05-02   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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