Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 660 [Rate centres in NPA 660] [Dial plan for NPA 660]

NXX: 598

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-598 A Rockville MO RKVLMOXADS0  1151 BRIGHTSPEED OF EAST MISSOURI, LLC 524      
660-598 0 Rockville MO   073H TELNYX LLC 524   2020-08-07   
660-598 2 Rockville MO   1151 BRIGHTSPEED OF EAST MISSOURI, LLC 524      
660-598 3 Rockville MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 524   2014-05-04   
660-598 4 Rockville MO   1151 BRIGHTSPEED OF EAST MISSOURI, LLC 524      
660-598 5 Rockville MO   093F ONVOY, LLC - MO 524   2018-10-29   
660-598 6 Rockville MO   1151 BRIGHTSPEED OF EAST MISSOURI, LLC 524      
660-598 7 Rockville MO   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524   2014-05-05   
660-598 9 Rockville MO   145J TERRA NOVA TELECOM INC. 524   2025-08-01   

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

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