Local Calling Guide

Area code/prefix search

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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 223

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-223 A Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 0 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 1 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 2 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 3 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 4 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 5 Old Mission MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2017-08-10   
231-223 6 Old Mission MI   145J TERRA NOVA TELECOM INC. 348   2025-07-12   
231-223 7 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 8 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      
231-223 9 Old Mission MI OLMSMIXIRS0  0720 ACE TEL. CO. OF MICHIGAN, INC. 348      

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

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