Where Is Area Code 779. Rockford is the largest city within this area code with a. 188 rows area code 779 serves the state of illinois. 779 Area Code - Location Map, Time Zone, And Phone Lookup from www.allareacodes.com On march 17th, 2007 it went into service. The 779 area code is located in the state of illinois. 779 Area Code - Location Map, Time Zone, And Phone Lookup Where is area code 779? Area code (779) is in the state of il. 283 rows area code 779.
