Area Code 603-309 located in FRANKLIN, MERRIMACK, NH, more detail is as below. Place NPA (Numbering Plan Area) : 603 NXX (Local Number Prefix) : 309 City : FRANKLIN County : MERRIMACK State : NH (New Hampshire) NXX Use Type : Landline NXX Intro Version : 1999-05-10 FIPS (Federal Information Processing Standards) : 33013 Rate Center : FRANKLIN ZIP Code Count : 0 ZIP Code Frequency : Most frequently occurring ZIP Code, although percentage is unknown. ZIP Code : 03235 Other Information NPANXX : 603309 County Population : 0 Switch CLLI (Common Language Location Identifier) : MNCHNHN1FF2 MSA CBSA (Core Based Statistical Area) : Concord, NH MSA CBSA Code (Core Based Statistical Area) : 18180 Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Latitude : None Longitude : None ‹ previous : 603-308 next › : 603-310 Telephone Number List 603-309-0000 ~ 603-309-9999