Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 256 [Rate centres in NPA 256] [Dial plan for NPA 256]

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
256-604 A Huntsville AL HNVIALODAMD  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 477      
256-604 0 Huntsville AL HNVIALODAMD  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 477      
256-604 1 Huntsville AL HNVIALUNXSY  5562 METROPCS, INC. 477   2007-07-26   
256-604 2 Huntsville AL HNVIALUNXSY  5562 METROPCS, INC. 477   2007-07-26   
256-604 3 Huntsville AL HNVIALODAMD  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 477   2010-04-17   
256-604 4 Huntsville AL HNVIALUNXSY  5562 METROPCS, INC. 477   2007-06-11   
256-604 5 Huntsville AL HNVIALUNXTZ  829J PAETEC ITEL, LLC 477   2005-03-20   
256-604 6 Huntsville AL HNVIALUNXSY  5562 METROPCS, INC. 477   2007-01-03   
256-604 7 Huntsville AL HNVIALUNXSY  5562 METROPCS, INC. 477   2007-01-03   
256-604 8 Huntsville AL HNVIALODAMD  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 477      
256-604 9 Huntsville AL HNVIALODAMD  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 477      

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

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