Below is a list of Modesto IL zip codes. For your research we have also included Modesto Area Code, Time Zone, UTC and the local Macoupin County FIPS Code. Each Modesto Illinois zip code has a center Longitude / Latitude point (the Modesto center is -89.982002258301 / 39.478199005127). For your convenience we have also indicated if that zip code in Modesto observes Daylight Savings time.