Below is a list of Posen IL zip codes. For your research we have also included Posen Area Code, Time Zone, UTC and the local Cook County FIPS Code. Each Posen Illinois zip code has a center Longitude / Latitude point (the Posen center is -87.686096191406 / 41.626098632812). For your convenience we have also indicated if that zip code in Posen observes Daylight Savings time.