Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Switch: BSWLOKMARS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
580-566 A Boswell OK 9533 SOUTHWESTERN BELL 536      
580-566 1 Boswell OK 9533 SOUTHWESTERN BELL 536      
580-566 2 Boswell OK 9533 SOUTHWESTERN BELL 536      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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