Below is a list of Washtenaw County MI zip codes. For your research we have also included Washtenaw County Area Code, Time Zone, UTC and the local County FIPS Code. Each Washtenaw County Michigan zip code has a center Longitude / Latitude point (the Washtenaw County center is -83.747100830078 / 42.254299163818). For your convenience we have also indicated if that zip code in Washtenaw County observes Daylight Savings time.