Local Calling Guide

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Alton, NH

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
603-855 A ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122      
603-855 2   314C IDT AMERICA, CORP. - NH 122   2009-12-18   
603-855 5   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2020-04-05   
603-855 8   145J TERRA NOVA TELECOM INC. 122   2025-07-11   
603-875 A ALTNNHXARP0  0049 UNION TEL. CO. 122      
603-875 0   0049 UNION TEL. CO. 122      
603-875 2   0049 UNION TEL. CO. 122      
603-875 3   0049 UNION TEL. CO. 122      
603-875 5   0049 UNION TEL. CO. 122      
603-875 6   0049 UNION TEL. CO. 122      
603-875 7   0049 UNION TEL. CO. 122      
603-875 9   0049 UNION TEL. CO. 122      

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

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