Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 810 [Rate centres in NPA 810] [Dial plan for NPA 810]

NXX: 637

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-637 A St Clair MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-637 0 St Clair MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2026-01-12   
810-637 1 St Clair MI   991E BANDWIDTH.COM CLEC, LLC - MI 340   2009-03-07   
810-637 2 St Clair MI   9714 GRID 4 COMMUNICATIONS, INC. - MI 340   2010-07-21   
810-637 3 St Clair MI   2550 123.NET, LLC 340   2003-01-24   
810-637 4 St Clair MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2004-01-17   
810-637 5 St Clair MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2005-05-29   
810-637 6 St Clair MI   829J PAETEC ITEL, LLC 340   2004-01-13   
810-637 7 St Clair MI   829J PAETEC ITEL, LLC 340   2009-10-26   
810-637 8 St Clair MI   318J COMCAST IP PHONE, LLC 340   2005-11-15   
810-637 9 St Clair MI   145J TERRA NOVA TELECOM INC. 340   2022-11-02   

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

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