Zip Area Code

Boone County, Illinois

Boone County, Illinois, has 8 towns and 5 ZIP codes, in area code 815, with 779 as an overlay.

Towns in Boone County, A to Z

TownZIP codesArea codes
Argylenearest61011, 61111, 61114815, 779
Belvidere61008815, 779
Caledonia61011815, 779
Candlewick Lakenearest61011, 61065815, 779
Capron61012815, 779
Garden Prairie61038815, 779
Poplar Grove61065815, 779
Timberlanenearest61011, 61065815, 779

ZIP codes in Boone County

Area codes in Boone County

  • Area code 815

    In service since 1947. Shares its area with 779. Local calls are dialed with 1 plus ten digits.

  • Area code 779

    In service since March 17, 2007. Shares its area with 815. Local calls are dialed with 1 plus ten digits.