Property tax in Washington County, Illinois
In Washington County, the property tax bill comes from the Washington County Treasurer and Collector. The 2025 payable 2026 bill is paid in 2 installments, and the next one is due October 16, 2026. You can look up and pay the bill on the county's own payment page. Taken from Washington County's own pages, checked September 23, 2026.
The median property tax bill in Washington County, Illinois is $2,908 a year, which is about 1.87% of the county's median home value of $155,700. That effective rate is higher than the typical Illinois county (1.81%) and higher than the national median (0.81%). These are American Community Survey 5-year estimates (2024); your own bill depends on your home's assessed value and any exemptions.
Who sends the property tax bill in Washington County, and how do you pay it?
The bill comes from the Washington County Treasurer and Collector. The value it is based on is set by a separate office, the Washington County Supervisor of Assessments, with the township and multi-township assessors, which is who to ask if the value looks wrong. For how to look up and pay the bill, go to the county's own payment information.
Township and multi-township assessors value homes, and the Supervisor of Assessments applies exemptions and serves as clerk of the Board of Review. A decision of the Board of Review can be appealed to the Illinois Property Tax Appeal Board within 30 days of the board's written decision. One county bill carries the taxes of every local district the property sits in, such as schools, the city or village, the township and fire or library districts. Payments can be made online, by mail, in person or in the drop box near the south entrance of the courthouse in Nashville (no cash in the drop box). Mobile homes get a separate bill, due June 30, 2026, that cannot be paid online or by card, with a late penalty of $25 a month up to $100. Not receiving a bill does not excuse late penalties.
When are property taxes due in Washington County?
For the 2025 payable 2026 bill, Washington County splits the bill into 2 payments, the first due September 11, 2026 and the last October 16, 2026. The next one due is the second installment, on October 16, 2026. An installment not paid by its due date is charged a penalty of 1.5% a month, or part of a month, starting the day after the due date, as state law sets; the increased amounts and the dates they apply are printed on the payment stubs. After Friday, December 18, 2026, online payments and personal or business checks are no longer accepted, only cash, a bank cashier's check or a money order. Taxes still unpaid are offered at the delinquent tax sale on Friday, January 22, 2027.
| Payment | Due | Note |
|---|---|---|
| First installment | September 11, 2026 (passed) | Bills for the 2025 tax year were mailed July 23, 2026. The county enforces the installment due dates, and a mailed payment counts as on time if it is postmarked by the due date. To pay the whole bill at once, send both payment stubs together; partial payments are not accepted. |
| Second installment | October 16, 2026 |
From Washington County's published schedule, checked September 23, 2026. If a date falls on a weekend or holiday, the county's own rules on the next business day apply.
Estimate the property tax on a home in Washington County
Enter a home's market value for a ballpark at Washington County's average effective rate of 1.87% (Census). The real bill depends on the home's assessed value, the millage where it sits and any exemptions.
Estimated property tax: $2,912 / year
Property tax in Washington County at a glance
| Measure | Value |
|---|---|
| Median annual property tax | $2,908 |
| Median home value | $155,700 |
| Effective tax rate | 1.87% |
| Typical Illinois county rate | 1.81% |
| National median county rate | 0.81% |
Effective rate = median real estate taxes paid divided by median home value. Source: U.S. Census Bureau, American Community Survey 5-year estimates.
How does Washington County compare in Illinois?
Among Illinois's 102 counties, Washington County has the 43rd highest effective property-tax rate: 42 rank higher and 59 rank lower. That is near the middle for Illinois. Nationally, it ranks 122nd of 3135 US counties by effective rate. See every Illinois county ranked.
How much do homeowners in Washington County actually pay?
The median is only the middle bill. Across Washington County's 4,874 owner-occupied homes, 47.1% pay $3,000 or more a year in property tax, 65.1% pay at least $2,000, and 11% pay under $800. Another 2.4% report paying no property tax at all, which usually means an exemption covers the whole bill.
| Annual bill | Homes | Share |
|---|---|---|
| Under $800 | 536 | 11% |
| $800 to $1,499 | 577 | 11.8% |
| $1,500 to $1,999 | 467 | 9.6% |
| $2,000 to $2,999 | 878 | 18% |
| $3,000 or more | 2,297 | 47.1% |
| No property tax paid | 119 | 2.4% |
Owners with a mortgage pay a median of $3,353 and owners without one pay $2,500. Owners who have paid off a home have usually held it longer, and in states that cap how fast an existing owner's assessment can rise, long-held homes carry lower assessed values. Census table B25103.
How does the Washington County property tax bill compare with local incomes?
The median property tax bill of $2,908 is about 3.5% of the median income of Washington County homeowner households, $83,992 a year. That compares two middles, so a retiree in a long-held home can pay a far larger share. 84.1% of Washington County's occupied homes are lived in by their owners; renters pay property tax too, just folded into rent.
Have property taxes gone up in Washington County?
Yes. The median bill went from $2,380 in 2015-2019 to $2,908 in 2020-2024, a 22.2% rise. Over the same span the median home value moved 37.2%, from $113,500 to $155,700. Bills rose more slowly than values, which is what assessment caps and falling millage rates do: the county is taxing a smaller share of each home's worth.
Two Census ACS 5-year periods with no survey years in common, in each period's own dollars. A change counts only if it exceeds the combined 90% margin of error.
Property tax in counties next to Washington County
Washington County borders 6 counties.
| County | Effective rate | Median bill | Median home value |
|---|---|---|---|
| St. Clair County, IL | 2.03% | $3,665 | $180,300 |
| Washington County, IL (this county) | 1.87% | $2,908 | $155,700 |
| Clinton County, IL | 1.83% | $3,524 | $192,400 |
| Marion County, IL | 1.71% | $1,759 | $103,000 |
| Jefferson County, IL | 1.7% | $2,148 | $126,000 |
| Perry County, IL | 1.6% | $1,807 | $112,600 |
| Randolph County, IL | 1.43% | $1,927 | $135,100 |
How is a home assessed in Washington County?
Illinois assesses homes at 33.33% of market value in every county, Washington County included. How Illinois assesses and reappraises homes.
Is there a homestead exemption in Washington County?
Yes. Illinois's General Homestead Exemption is $6,000 of equalized assessed value in most counties, $8,000 in counties next to Cook, and $10,000 in Cook County. That is the Illinois rule, and it applies in Washington County. Illinois's exemptions and relief programs in full.
Washington County does not add relief programs of its own beyond the Illinois ones (checked September 23, 2026).
How to appeal your Washington County property assessment
In Washington County you appeal to the Washington County Board of Review. The deadline: Under state law, a written complaint must be filed with the Board of Review within 30 calendar days after the county publishes the assessment list for the year, and a mailed complaint counts as filed on its postmark date. The county has not posted the date for 2026 assessments; the Supervisor of Assessments, who is also clerk of the Board of Review, can give the exact deadline. How to file. Checked September 23, 2026 against state law, because Washington County does not restate them on its own pages.
How Illinois's appeal process works, including the next level if the first one turns you down.
Illinois rules from primary state sources, reviewed September 7, 2026; sources on the Illinois page.
Work out your own numbers
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How much house can I afford?
Your income, debts and down payment against the 28/36 rule lenders actually use, with Washington County's tax rate to hand.
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Mortgage calculator
Monthly payment with principal, interest, tax and insurance, plus what an extra payment saves you.
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Illinois income tax
Brackets, standard deduction and what Illinois actually taxes.
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Sales tax in Washington County
The other local tax: combined state and local rate for this county.
Sources
- Median real estate taxes paid and median home value for Washington County, Illinois: U.S. Census Bureau, American Community Survey 5-year estimates (2020-2024), tables B25103, B25077, B25102, B25119 and B25003; the five-year comparison uses the 2015-2019 estimates. Neighboring counties: Census county adjacency file.