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: ARGYMOPARS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
573-728 A Argyle MO 9533 SOUTHWESTERN BELL 521      
573-728 1 Argyle MO 9533 SOUTHWESTERN BELL 521      
573-728 6 Argyle MO 9533 SOUTHWESTERN BELL 521      
573-728 9 Argyle MO 9533 SOUTHWESTERN BELL 521      

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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