Washington is a city located in Tazewell County, Illinois, within the United States. Situated northeast of East Peoria, the city sits along U.S. Route 24 and Illinois Route 8.
The city serves as a suburb of Peoria and is integrated into the Peoria Metropolitan Statistical Area. According to the 2020 census, Washington had a population of 16,071, which represented a 48.2 percent increase since the year 2000.