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: GTBGMDGBPS0

Remotes:

Switch Switch name Switch type
CHCHMDBERP0  CHEVY CHASE  RP 
DMSCMDDERP0    RP 
NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
240-276 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
240-386 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
240-631 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
240-632 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
240-683 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-208 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-212 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-216 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-240 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-258 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-330 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-355 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-417 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-519 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-527 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-548 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-590 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-640 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-670 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-721 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-740 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-840 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-869 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-921 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-926 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-947 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-948 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-956 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-963 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-975 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-977 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-978 A Washington Zone 10 MD 9212 VERIZON MARYLAND, INC. 236      
301-987 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      
301-990 A Gaithersburg MD 9212 VERIZON MARYLAND, INC. 236      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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