Below is a list of Williamson PA zip codes. For your research we have also included Williamson Area Code, Time Zone, UTC and the local Franklin County FIPS Code. Each Williamson Pennsylvania zip code has a center Longitude / Latitude point (the Williamson center is -77.799499511719 / 39.853401184082). For your convenience we have also indicated if that zip code in Williamson observes Daylight Savings time.