Area Code 203-903 located in NEW HAVEN, NEW HAVEN, CT, more detail is as below. Place NPA (Numbering Plan Area) : 203 NXX (Local Number Prefix) : 903 City : NEW HAVEN County : NEW HAVEN State : CT (Connecticut) NXX Use Type : Landline NXX Intro Version : 2001-06-30 FIPS (Federal Information Processing Standards) : 09009 LATA (Local Access Transport Area) : 920 Rate Center : NEW HAVEN ZIP Code Count : 0 ZIP Code Frequency : Most frequently occurring ZIP Code, although percentage is unknown. ZIP Code : 06511 Other Information NPANXX : 203903 County Population : 0 Switch CLLI (Common Language Location Identifier) : SMFRCTPUDS0 MSA CBSA (Core Based Statistical Area) : New Haven-Milford, CT MSA CBSA Code (Core Based Statistical Area) : 35300 Time Zone : Eastern (GMT -05:00) Observes Daylight Saving Time : Yes Company : LEVEL 3 COMMUNICATIONS, LLC - CT OCN (Operating Company Number) : 4800 Coverage Area Name : NEW HAVEN Latitude : 41.3114 Longitude : -72.9161 ‹ previous : 203-903 next › : 203-904 Telephone Number List 203-903-0000 ~ 203-903-9999