Area Code 773-240 located in CHICAGO, COOK, IL, more detail is as below. Place NPA (Numbering Plan Area) : 773 NXX (Local Number Prefix) : 240 City : CHICAGO County : COOK State : IL (Illinois) NXX Use Type : Wireless NXX Intro Version : 10/16/2007 FIPS (Federal Information Processing Standards) : 17031 LATA (Local Access Transport Area) : 358 Rate Center : CHICGOZN10 ZIP Code Count : 0 ZIP Code Frequency : 0 ZIP Code : 60643 Other Information NPANXX : 773240 MSA CBSA (Core Based Statistical Area) : Chicago-Naperville-Joliet, IL-IN-WI MSA CBSA Code (Core Based Statistical Area) : 16980 Time Zone : Central (GMT -06:00) Observes Daylight Saving Time : Yes Company : T-MOBILE USA, INC. OCN (Operating Company Number) : 6529 Coverage Area Name : CHICAGO Latitude : 41.6961 Longitude : -87.6384 ‹ previous : 773-239 next › : 773-241 Telephone Number List 773-240-0000 ~ 773-240-9999