
Washington
- County:
- Tazewell County
- County Seat:
- No
- Area (mi²):
- 8.55
- State:
- Illinois
Washington is a city located in Tazewell County, Illinois. Washington has a 2025 population of 15,685. Washington is currently declining at a rate of -0.47% annually and its population has decreased by -2.3% since the most recent census, which recorded a population of 16,055 in 2020.
The average household income in Washington is $108,978 with a poverty rate of 4.75%. The median age in Washington is 37.3 years: 36.5 years for males, and 38.5 years for females.