Below is a list of Hillsdale IL zip codes. For your research we have also included Hillsdale Area Code, Time Zone, UTC and the local Rock Island County FIPS Code. Each Hillsdale Illinois zip code has a center Longitude / Latitude point (the Hillsdale center is -90.174697875977 / 41.61360168457). For your convenience we have also indicated if that zip code in Hillsdale observes Daylight Savings time.