Local Calling Guide

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NPA: 608 [Rate centres in NPA 608] [Dial plan for NPA 608]

NXX: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
608-421 A Madison WI MDSNWI11XYX  551G NUSO, LLC 354      
608-421 0 Madison WI   6529 T-MOBILE USA, INC. 354   2013-10-14   
608-421 1 Madison WI   551G NUSO, LLC 354   2013-05-08   
608-421 2 Madison WI   6529 T-MOBILE USA, INC. 354   2013-08-05   
608-421 3 Madison WI   6529 T-MOBILE USA, INC. 354   2013-08-05   
608-421 4 Madison WI   6529 T-MOBILE USA, INC. 354   2013-08-05   
608-421 5 Madison WI   7322 LEVEL 3 TELECOM OF WISCONSIN, LP - WI 354   2013-08-22   
608-421 6 Madison WI   7216 TELEPORT COMMUNICATIONS AMERICA, LLC WI 354   2013-09-09   
608-421 7 Madison WI   7216 TELEPORT COMMUNICATIONS AMERICA, LLC WI 354   2013-09-09   
608-421 8 Madison WI   6529 T-MOBILE USA, INC. 354   2013-10-14   
608-421 9 Madison WI   6529 T-MOBILE USA, INC. 354   2013-10-14   

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

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