Area Code 240-308 located in CLARKSBURG, MONTGOMERY, MD, more detail is as below. Place NPA (Numbering Plan Area) : 240 NXX (Local Number Prefix) : 308 City : CLARKSBURG County : MONTGOMERY State : MD (Maryland) NXX Use Type : Wireless NXX Intro Version : 2000-08-20 FIPS (Federal Information Processing Standards) : 24031 LATA (Local Access Transport Area) : 236 Rate Center : DAMASCS236 ZIP Code Count : 0 ZIP Code Frequency : Most frequently occurring ZIP Code, although percentage is unknown. ZIP Code : 20871 Other Information NPANXX : 240308 County Population : 0 Switch CLLI (Common Language Location Identifier) : WASHDCDTX6X 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 : NEW CINGULAR WIRELESS PCS, LLC - DC OCN (Operating Company Number) : 4036 Coverage Area Name : DAMASCUS Latitude : 39.2904 Longitude : -77.2083 ‹ previous : 240-308 next › : 240-309 Telephone Number List 240-308-0000 ~ 240-308-9999