Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 824J OPENTACT INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
983-277 A Denver CO   656   2026-03-09   
983-277 4 Denver CO   656   2026-03-09   

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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