Local Calling Guide

Area code/prefix search

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NPA: 771 [Rate centres in NPA 771] [Dial plan for NPA 771]

NXX: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
771-231 A Washington Zone 1 DC WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
771-231 0 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 1 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 2 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 3 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 4 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 5 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 6 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 7 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 8 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   
771-231 9 Washington Zone 1 DC   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2023-05-28   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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