Below is a list of Oswego IL zip codes. For your research we have also included Oswego Area Code, Time Zone, UTC and the local Kendall County FIPS Code. Each Oswego Illinois zip code has a center Longitude / Latitude point (the Oswego center is -88.336402893066 / 41.690700531006). For your convenience we have also indicated if that zip code in Oswego observes Daylight Savings time.