Property tax in Clay County, Illinois
In Clay County, the property tax bill comes from the Clay County Treasurer. The 2025 Payable in 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 Clay County's own pages, checked September 23, 2026.
The median property tax bill in Clay County, Illinois is $1,392 a year, which is about 1.43% of the county's median home value of $97,400. That effective rate is lower 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 Clay County, and how do you pay it?
The bill comes from the Clay County Treasurer. The value it is based on is set by a separate office, the Clay 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; the county encourages owners to talk with the Supervisor of Assessments before filing a complaint, and a Board of Review decision can be appealed to the Illinois Property Tax Appeal Board within 30 days of its final notice. 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. Online card payments go through a payment vendor and carry a convenience fee the county does not keep. Payments can also be mailed to the Clay County Treasurer, P.O. Box 88, Louisville, IL 62858, made in person at the courthouse, or left in the drop box. Mobile homes get a separate bill, due July 1, 2026, with a $25 a month late penalty up to $100, and unpaid mobile home taxes are still sold to private tax buyers. Not receiving a bill does not excuse late penalties.
When are property taxes due in Clay County?
For the 2025 Payable in 2026 bill, Clay County splits the bill into 2 payments, the first due October 16, 2026 and the last November 20, 2026. Starting the day after each due date, state law adds a penalty of 1.5% a month, and part of a month counts as a whole month. When delinquent notices are mailed, $10 is added to each bill for certified mail and publication, as state law provides. Late taxes and penalties can be paid up to the tax sale. Starting with the sale for 2025 taxes, the county takes over all unpaid real estate taxes as trustee for the local taxing districts instead of offering them to private tax buyers; the county's older question-and-answer section still describes a sale to tax buyers, but that no longer applies to real estate. After the sale, back taxes are paid off through the County Clerk by cashier's check, money order or cash, not personal check.
| Payment | Due | Note |
|---|---|---|
| First installment | October 16, 2026 | Bills were mailed September 11, 2026. The whole bill can be paid by this date without penalty; paying it all after this date adds a penalty even if paid before the second due date. Under state law, a mailed payment postmarked by the due date is on time. |
| Second installment | November 20, 2026 |
From Clay 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 Clay County
Enter a home's market value for a ballpark at Clay County's average effective rate of 1.43% (Census). The real bill depends on the home's assessed value, the millage where it sits and any exemptions.
Estimated property tax: $1,393 / year
Property tax in Clay County at a glance
| Measure | Value |
|---|---|
| Median annual property tax | $1,392 |
| Median home value | $97,400 |
| Effective tax rate | 1.43% |
| 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 Clay County compare in Illinois?
Among Illinois's 102 counties, Clay County has the 90th highest effective property-tax rate: 89 rank higher and 12 rank lower. That places it among the least taxed counties in the state. Nationally, it ranks 427th of 3135 US counties by effective rate. See every Illinois county ranked.
How much do homeowners in Clay County actually pay?
The median is only the middle bill. Across Clay County's 4,211 owner-occupied homes, 17.1% pay $3,000 or more a year in property tax, 32.7% pay at least $2,000, and 32.2% pay under $800. Another 6.5% report paying no property tax at all, which usually means an exemption covers the whole bill.
| Annual bill | Homes | Share |
|---|---|---|
| Under $800 | 1,356 | 32.2% |
| $800 to $1,499 | 722 | 17.1% |
| $1,500 to $1,999 | 483 | 11.5% |
| $2,000 to $2,999 | 655 | 15.6% |
| $3,000 or more | 722 | 17.1% |
| No property tax paid | 273 | 6.5% |
Owners with a mortgage pay a median of $1,792 and owners without one pay $839. 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 Clay County property tax bill compare with local incomes?
The median property tax bill of $1,392 is about 2% of the median income of Clay County homeowner households, $70,350 a year. That compares two middles, so a retiree in a long-held home can pay a far larger share. 79.3% of Clay 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 Clay County?
The survey cannot tell. The median bill was $1,445 in 2015-2019 and $1,392 in 2020-2024, but that $53 difference is inside the Census's own margin of error for a county this size, so it could be sampling noise rather than a real change.
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 Clay County
Clay County borders 6 counties.
| County | Effective rate | Median bill | Median home value |
|---|---|---|---|
| Jasper County, IL | 1.95% | $2,448 | $125,500 |
| Marion County, IL | 1.71% | $1,759 | $103,000 |
| Richland County, IL | 1.58% | $1,769 | $112,000 |
| Effingham County, IL | 1.49% | $2,823 | $189,500 |
| Wayne County, IL | 1.49% | $1,653 | $110,700 |
| Fayette County, IL | 1.45% | $1,894 | $130,700 |
| Clay County, IL (this county) | 1.43% | $1,392 | $97,400 |
How is a home assessed in Clay County?
Illinois assesses homes at 33.33% of market value in every county, Clay County included. How Illinois assesses and reappraises homes.
Is there a homestead exemption in Clay 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 Clay County. Illinois's exemptions and relief programs in full.
Clay County does not add relief programs of its own beyond the Illinois ones (checked September 23, 2026).
How to appeal your Clay County property assessment
In Clay County you appeal to the Clay County Board of Review. The deadline: A written complaint on the state form, with all supporting evidence, must be filed within 30 calendar days of the date the assessments are published; a mailed complaint must be postmarked by the deadline. The county has not posted the 2026 publication date; the Supervisor of Assessments, who is clerk of the Board of Review, can give it. How to file. Checked September 23, 2026 against the official appeal rules.
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 Clay 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 Clay County
The other local tax: combined state and local rate for this county.
Sources
- Median real estate taxes paid and median home value for Clay 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.