Area Code 410-217 located in ROCKVILLE, MONTGOMERY, MD, more detail is as below. Place NPA (Numbering Plan Area) : 410 NXX (Local Number Prefix) : 217 City : ROCKVILLE County : MONTGOMERY State : MD (Maryland) NXX Use Type : Wireless NXX Intro Version : 1996-04-15 FIPS (Federal Information Processing Standards) : 24031 LATA (Local Access Transport Area) : 238 Rate Center : BALTIMORE ZIP Code Count : 1 ZIP Code Frequency : 100 ZIP Code : 20850 Other Information NPANXX : 410217 Switch CLLI (Common Language Location Identifier) : BLTMMDCH1DD 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 : BALTIMORE Latitude : 39.2938 Longitude : -76.6132 ‹ previous : 410-216 next › : 410-218 Telephone Number List 410-217-0000 ~ 410-217-9999