Livingston County is a county located in the U.S. state of Illinois. According to the 2020 census, it has a population of 35,815. Its county seat is Pontiac. Livingston County comprises the Pontiac, IL Micropolitan Statistical Area, which is combined with the Bloomington–Normal metropolitan statistical area as the Bloomington-Pontiac, IL Combine…Livingston County is a county located in the U.S. state of Illinois. According to the 2020 census, it has a population of 35,815. Its county seat is Pontiac. Livingston County comprises the Pontiac, IL Micropolitan Statistical Area, which is combined with the Bloomington–Normal metropolitan statistical area as the Bloomington-Pontiac, IL Combined Statistical Area in upper portion of Central Illinois.