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.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: NGLNCOMADS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
303-252 A Denver CO 9636 QWEST CORPORATION 656      
303-254 A Denver CO 9636 QWEST CORPORATION 656      
303-255 A Denver CO 9636 QWEST CORPORATION 656      
303-280 A Denver CO 9636 QWEST CORPORATION 656      
303-450 A Denver CO 9636 QWEST CORPORATION 656      
303-451 A Denver CO 9636 QWEST CORPORATION 656      
303-452 A Denver CO 9636 QWEST CORPORATION 656      
303-453 A Denver CO 9636 QWEST CORPORATION 656      
303-457 A Denver CO 9636 QWEST CORPORATION 656      
303-538 A Denver CO 9636 QWEST CORPORATION 656      
303-920 A Denver CO 9636 QWEST CORPORATION 656      
720-627 A Denver CO 9636 QWEST CORPORATION 656      
720-872 A Denver CO 9636 QWEST CORPORATION 656      
720-929 A Denver CO 9636 QWEST CORPORATION 656      
720-972 A Denver CO 9636 QWEST CORPORATION 656      
720-977 A Denver CO 9636 QWEST CORPORATION 656      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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