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 · High bill
- 1.72%
- Effective rate · Highest-decile 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 (Census ACS 2024).
- $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. Population: 66,876. 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.
Williamson County's rate standing among U.S. counties
Primary signal
The effective rate is a national headwind
Williamson County's 1.72% effective rate is among the highest of 3,135 tracked counties: only about 94% pay more.
Decision signal 2
The bill sits well above the national median
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.
Decision signal 3
Income and the tax bill sit in the middle band
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.
Decision signal 4
Near the middle of Illinois counties by effective rate
Williamson County ranks #61 of 102 counties in Illinois by effective rate (40% of in-state counties pay a lower rate).
Informational notice
Figures describe the median homeowner household in Williamson County as reported to the Census Bureau; your parcel can differ. Not tax, legal, or financial advice: check the county assessor or a qualified professional before decisions that depend on these numbers.
The rate held while the market moved
Williamson County sits in the quarter of U.S. counties whose effective rate moved least over this span: 5.3% up, against a median home value that rose 29.4%.
A near-steady rate on a moving market passes that movement straight through: the median bill rose 36.2%, from $1,975 to $2,690.
Effective rate is the published median bill divided by the published median home value, so the two multiply back to the bill exactly; the rate's movement here is derived from those two figures rather than read from the rounded published rate. Both are ACS 5-year survey estimates for the median owner-occupied household, compared across non-overlapping releases. They describe what the Census published, not a local policy, assessment, or exemption change.
How to read this county's bill
The bill here climbed steeply over 2020-2024, up 36% from $1,975 to $2,690. These ACS medians describe the reported change; they do not identify whether a levy, assessment, home value, or change in the responding households caused it.
The heaviest band is also the fullest one here: 8,608 of 20,477 owner-occupied homes (42.0%) report annual real-estate taxes above $3,000. That band has no upper edge in the source, so the county median understates the burden carried by the plurality rather than describing it.
A top-quartile rate meets below-median earnings here, and the median bill reaches 4.1% of median household income. A rate ranking places this county by the rate alone; the ratio above is the figure that accounts for what is earned here.
The share above is the median annual bill divided by median household income, a ratio of two county-level medians rather than a household-by-household figure.
What Williamson County Homeowners Actually Pay
The single largest group of Williamson County homeowners, 8,608 of 20,477 owner-occupied homes (42.0%), pays $3,000 or more a year. The median is one point in this spread, not a typical bill.
- Less than $800 11.1% (2,283)
- $800 to $1,499 14.3% (2,923)
- $1,500 to $1,999 9.8% (1,999)
- $2,000 to $2,999 18.0% (3,696)
- $3,000 or more 42.0% (8,608)
Census ACS 2024, table B25102. Bands and the no-tax share sum to 100%.
968 homes here (4.7%) report no real estate tax at all. Exemptions are set by state: how Illinois handles assessments and appeals.
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.
Williamson County's effective rate vs peers
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.
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
Show national distribution
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
Among the highest-taxed counties in the country
At 1.72%, Williamson County sits in the top 6% of all U.S. counties by effective property-tax rate. That is the rate, not the bill: a high rate on a modest home can still produce a smaller cheque than a low rate on an expensive one, which is why the $2,690 median bill is the number to compare against another county.
Williamson County vs Benchmarks
| Metric | Williamson County | Illinois Avg | U.S. Avg |
|---|---|---|---|
| Median Annual Tax High bill | |||
| Effective Tax Rate Highest-decile rate | |||
| Median Home Value | |||
| Tax as % of income Heavy income burden | 4.1% | - | - |
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.
Williamson County's STEEP · MID lane - is an appeal worth running?
On Williamson County's published figures (STEEP · MID), a $156,400 median home carries a $2,690 median bill, so every 10% off an assessed value is worth about $269 a year at the same rate. Appeal Savings Estimator · appeal guide for Illinois.
Williamson County rate trail · STEEP
| Year | Median Tax (vs prior release) | 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% |
Each row is a separate ACS 5-year release, and consecutive releases share four of their five survey years. The percentage beside each bill is therefore movement in the published estimate against the previous release, not a single year's tax change. The two releases largely describe the same households. For change over time, compare releases that do not overlap.
Williamson County: tax takes 4.1% of income
Counties near Williamson County's effective rate
On effective rate, Williamson County sits nearest Dillingham Census Area (AK), Montgomery County (KS), Grafton County (NH).
On published median-tax change, the nearest matches are Davidson County (TN), Tattnall County (GA), Casey County (KY).
How peers are chosen
These are the nearest cross-state matches in the published Census data, not neighboring counties or recommendations. Peers are rebuilt with each data release; see the calculation method.
Similar effective rates
Similar published median-tax changes, 2020–2024
Williamson County: only 3% of returns show Schedule A real-estate tax
Tax year 2022: 980 of 30,200 returns from Williamson County reported real estate taxes, averaging $5,704 - 35% of those reporters sat in the $100-200k AGI band.
What this IRS county file does not say
Amounts are reported before the SALT cap, not deducted; the share is of filers, not homeowners. Source: IRS SOI county data, tax year 2022.
Other Counties in Illinois
Williamson County rate FAQs
- What is the tax affordability score for Williamson County?
- Williamson County, Illinois scores F (18/100) on PlainPropertyTax's tax affordability composite across 5 Census ACS dimensions (effective rate, bill size, income share, mortgage gap, and home-value/income). Its strongest scored dimension here is housing pressure at B+ (2.38×). The score compares published county medians to U.S. percentiles, it is not a personal bill and not advice to buy, sell, appeal, or relocate.
- How does Williamson County property tax compare to the national average?
- Property taxes in Williamson County run well above the national median of $1,993, an effective rate of 1.72% versus 0.92% nationally.
- What is the average property tax in Williamson County, Illinois?
- The median annual property tax in Williamson County is $2,690, an effective rate of 1.72% on a $156,400 median home (Census ACS, 2024).
- Are property taxes increasing in Williamson County?
- The ACS median property-tax bill for Williamson County jumped 36.2% between the 2020 and 2024 5-year releases, from $1,975 to $2,690, a 4-year span. These are survey estimates covering five years each, so this compares the two releases furthest apart rather than consecutive ones, which overlap and would mostly measure the same households twice.
- What percentage of income goes to property taxes in Williamson County?
- 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.
What to do with Williamson County's STEEP rate
Williamson County's $2,690 median bill sits well above the U.S. median - size a personal estimate before treating the county headline as your budget. Estimate your bill →
Williamson County ranks #61 of 102 Illinois counties by effective rate - on the lower-burden half of the state ACS set. Illinois overview →
Nationwide peers by effective rate (then bill)
Rate-first peers for Williamson County's STEEP effective rate, then a disjoint out-of-state bill set so the two neighborhoods stay distinct.
Similar effective rate
Nearest out-of-state counties by ACS effective rate. This county: 1.72%.
Similar median bill
Nearest out-of-state counties by ACS median annual tax. This county: $2,690/yr. Rate peers are excluded so the two link sets stay distinct.
Read with Williamson County
Nearest ABS(median_tax) ACS peers for Williamson County (STEEP · MID), replacing the old fixed Keep exploring strip.
STEEP MID
Otoe County, NE
ABS(median_tax) peer · $2,691/yr (near-tied bill ABS $1); rate 1.33% vs Williamson County 1.72%.
Whitman County, WA
ABS(median_tax) peer · $2,691/yr (near-tied bill ABS $1); rate 0.75% vs Williamson County 1.72%.
Lewis County, NY
ABS(median_tax) peer · $2,688/yr (near-tied bill ABS $2); rate 1.62% vs Williamson County 1.72%.
Morton County, ND
ABS(median_tax) peer · $2,686/yr (near-tied bill ABS $4); rate 1.02% vs Williamson County 1.72%.
Illinois county set
State ACS overview for every published Illinois county rate and median bill.
Appeal filing windows
Williamson County stamps STEEP · MID - review notice deadlines before quoting the ACS median.
Data vintage and method
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.
Source: U.S. Census Bureau American Community Survey 5-Year Estimates, county median real-estate taxes · 2024 Williamson County (STEEP · MID) - ACS medians, not a parcel bill.