Area Code 240-204 located in CHEVY CHASE, MONTGOMERY, MD, more detail is as below. Place NPA (Numbering Plan Area) : 240 NXX (Local Number Prefix) : 204 City : CHEVY CHASE County : MONTGOMERY State : MD (Maryland) NXX Use Type : Wireless NXX Intro Version : 9/7/2011 FIPS (Federal Information Processing Standards) : 24031 LATA (Local Access Transport Area) : 236 Rate Center : WSHNGTNZN2 ZIP Code Count : 0 ZIP Code Frequency : 0 ZIP Code : 20815 Other Information NPANXX : 240204 County Population : 0 MSA CBSA (Core Based Statistical Area) : Washington-Arlington-Alexandria, DC-VA-MD-WV MSA CBSA Code (Core Based Statistical Area) : 47900 Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Overlay : L Company : CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD OCN (Operating Company Number) : 6395 Coverage Area Name : BETHESDA Latitude : 38.9858 Longitude : -77.1065 ‹ previous : 240-203 next › : 240-205 Telephone Number List 240-204-0000 ~ 240-204-9999