Illinois · County property tax · ACS 2024
Williamson County Property Taxes
The median homeowner in Williamson County pays $2,690 a year, an effective rate of 1.72%, well above the U.S. average.
- $2,690
- Median tax / yr
- 1.72%
- Effective rate
- +35%
- vs U.S. average
- #61 of 102
- rank in IL
The verdict
Homeowners in Williamson County pay a median $2,690 a year in property tax, an effective rate of 1.72%, more affordable than 6% of U.S. counties.
- $2,690
- Median annual tax bill, 2024
- 1.72%
- Effective rate on median home
- #2959 of 3135
- U.S. counties by tax burden
- +35%
- vs the national average bill
Effective rate is the median property tax bill divided by the median home value ($156,400). U.S. Census Bureau, ACS 5-Year Estimates · 2024.
Census Bureau ACS property tax data for Illinois. Owner-occupied homes: 20,477.
The median annual property tax in Williamson County is $2,690, which is 49% lower than the Illinois state average and 35% above the national average. The effective tax rate is 1.72% on a median home value of $156,400. Property taxes represent 4.1% of the median household income in this county.
What This Data Tells Us About Williamson County
Homeowners in Williamson County pay a median annual property tax of $2,690, well above the national median and well below the Illinois state median. On a $156,400 median home, that works out to an effective rate of 1.72% once the local assessment base and millage are combined.
Property taxes in Williamson County run a bit above the commonly cited 2%-4% national benchmark, at about 4.1% of the $65,604 median household income. Since 2023, the published ACS median estimate has climbed 8.0%, from $2,490 to $2,690. This compares two release estimates; it does not identify a local policy, assessment, exemption, or household-bill cause.
This page is for informational purposes only and is not tax, legal, or financial advice. Figures describe the median homeowner household in Williamson County as reported to the Census Bureau, your own bill can differ based on your parcel's assessed value, exemptions, special districts, and municipal overlays. Always consult your county assessor, tax collector, or a qualified professional before making decisions that depend on these numbers.
With vs Without Mortgage
Mortgaged homeowners in Williamson County pay a substantially higher bill, 52% more, pointing to a wide home-value gap between the two groups.
How Williamson County compares
Effective property tax rate (median tax ÷ median home value), ACS 2024.
Williamson County's effective rate is higher than 40% of the 102 counties in Illinois - ranking #61 of 102 for property tax burden.
Where Williamson County sits among every U.S. county
Effective property tax rate (median tax ÷ median home value)
1.72% more affordable than 6% of 3,135 U.S. counties
Each bar is a band; taller bars hold more U.S. counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Census Bureau, ACS 5-Year Estimates · 2024
Williamson County vs Benchmarks
| Metric | Williamson County | Illinois Avg | U.S. Avg |
|---|---|---|---|
| Median Annual Tax | $2,690 | $5,298 | $1,993 |
| Effective Tax Rate | 1.72% | 2.01% | 0.92% |
| Median Home Value | $156,400 | $263,300 | $227,791 |
Source: U.S. Census Bureau, ACS 5-Year Estimates. Tax-burden differences across rows reflect millage decisions, assessment-ratio practices, and the residential-vs-commercial mix of each tax base.
Think your Williamson County property tax bill is too high?
A successful appeal can lower your assessed value by 10-25%, cutting your annual tax bill by hundreds or thousands of dollars. Use our free Appeal Savings Estimator to project savings on your specific home, then read our step-by-step appeal guide for the exact procedure in Illinois.
Property Tax History
| Year | Median Tax | Effective Rate |
|---|---|---|
| 2024 | $2,690 +8.0% | 1.72% |
| 2023 | $2,490 +6.5% | 1.71% |
| 2022 | $2,337 +8.9% | 1.68% |
| 2021 | $2,146 +8.7% | 1.71% |
| 2020 | $1,975 | 1.63% |
Tax Burden
Tax Affordability Score
An effective rate far above the national average of 0.92% puts Williamson County in the "Very Expensive" band for property tax burden.
How this score is calculated: a 1-10 scale derived mechanically from the ratio of this county's effective rate to the national average effective rate (0.92%) - a ratio at or below 0.5× scores 10, a ratio at or above 2.0× scores 1, with a linear scale between. It is a factual comparison of Census figures only, not a recommendation, quality rating, or endorsement of Williamson County or any other county.
Other Counties in Illinois
Frequently Asked Questions
What is the average property tax in Williamson County, Illinois? ▼
How does Williamson County property tax compare to the national average? ▼
What percentage of income goes to property taxes in Williamson County? ▼
Are property taxes increasing in Williamson County? ▼
What this means in Williamson County
How to use Williamson County's property-tax numbers, for budgeting, comparison, or an appeal.
- At Williamson County's 1.72% effective rate, a $156,400 home implies about $2,690/yr, plug in your own home's value to estimate your bill. Estimate your bill
- Williamson County ranks #61 of 102 counties in Illinois by effective rate, compare it against the rest of the state before you judge your bill. Illinois overview
- If your assessed value looks high relative to Williamson County's typical home, you may have grounds to appeal, most jurisdictions have a filing window each year. How to appeal
Effective rate is the county median tax divided by the county median home value ($156,400); your parcel's assessed value, exemptions, and local levies determine your actual bill. U.S. Census Bureau ACS · 2024.
Data as of 2024. Source: U.S. Census Bureau, American Community Survey 5-Year Estimates.
Property tax data reflects median amounts paid by homeowners. Effective rates are calculated as median tax divided by median home value.
PlainPropertyTax is rendered directly from the U.S. Census Bureau's American Community Survey (ACS) 5-year estimates, no number is typed in by an editor. This page draws directly on the Census ACS county-level record for Williamson County. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-06-09.