Below is a list of Gallatin County IL zip codes. For your research we have also included Gallatin County Area Code, Time Zone, UTC and the local County FIPS Code. Each Gallatin County Illinois zip code has a center Longitude / Latitude point (the Gallatin County center is -88.234298706055 / 37.778701782227). For your convenience we have also indicated if that zip code in Gallatin County observes Daylight Savings time.