Below is a list of Grantsburg IL zip codes. For your research we have also included Grantsburg Area Code, Time Zone, UTC and the local Johnson County FIPS Code. Each Grantsburg Illinois zip code has a center Longitude / Latitude point (the Grantsburg center is -88.747001647949 / 37.390998840332). For your convenience we have also indicated if that zip code in Grantsburg observes Daylight Savings time.