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: BLTMMDCHXFX

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
240-755 A Laurel (Baltimore LATA) MD 318J COMCAST IP PHONE, LLC 238      
301-327 A Washington Zone 15 (Baltimore LATA) MD 318J COMCAST IP PHONE, LLC 238      
410-497 A Parkville MD 318J COMCAST IP PHONE, LLC 238      
410-870 A Parkville MD 318J COMCAST IP PHONE, LLC 238      
443-275 A Towson MD 318J COMCAST IP PHONE, LLC 238      
443-379 A Pikesville MD 318J COMCAST IP PHONE, LLC 238      
443-456 A Edgewood MD 318J COMCAST IP PHONE, LLC 238      
443-542 A Columbia MD 318J COMCAST IP PHONE, LLC 238      
443-559 A Essex MD 318J COMCAST IP PHONE, LLC 238      
443-660 A Pikesville MD 318J COMCAST IP PHONE, LLC 238      
443-949 A Annapolis MD 318J COMCAST IP PHONE, LLC 238      
667-215 A Elkton MD 318J COMCAST IP PHONE, LLC 238      

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

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