Area Code 712-439 located in DOON, LYON, IA, more detail is as below. Place NPA (Numbering Plan Area) : 712 NXX (Local Number Prefix) : 439 City : DOON County : LYON State : IA (Iowa) NXX Use Type : Landline NXX Intro Version : 1994-02-04 FIPS (Federal Information Processing Standards) : 19119 LATA (Local Access Transport Area) : 630 Rate Center : HULL ZIP Code Count : 34 ZIP Code Frequency : 3 ZIP Code : 51235 Other Information NPANXX : 712439 Switch CLLI (Common Language Location Identifier) : HULLIAACRS4 Time Zone : Central (GMT -06:00) Observes Daylight Saving Time : Yes Company : HEARTLAND TELECOM COMPANY OF IOWA DBA HICKORYTECH OCN (Operating Company Number) : 1109 Coverage Area Name : HULL Latitude : 43.1879 Longitude : -96.1336 ‹ previous : 712-439 next › : 712-439 Telephone Number List 712-439-0000 ~ 712-439-9999