Area Code 301-228 located in FREDERICK, FREDERICK, MD, more detail is as below. Place NPA (Numbering Plan Area) : 301 NXX (Local Number Prefix) : 228 City : FREDERICK County : FREDERICK State : MD (Maryland) NXX Use Type : Landline NXX Intro Version : 1997-07-06 FIPS (Federal Information Processing Standards) : 24021 LATA (Local Access Transport Area) : 240 Rate Center : FREDERICK ZIP Code Count : 116 ZIP Code Frequency : 27 ZIP Code : 21702 Other Information NPANXX : 301228 County Population : 0 Switch CLLI (Common Language Location Identifier) : FRDRMDFRDS0 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 Company : VERIZON MARYLAND, INC. OCN (Operating Company Number) : 9212 Coverage Area Name : FREDERICK Latitude : 39.4148 Longitude : -77.4123 ‹ previous : 301-227 next › : 301-228 Telephone Number List 301-228-0000 ~ 301-228-9999