Williamson County, Illinois Property Taxes
Property Taxes in Williamson County, Illinois
Median Williamson County effective property tax rate: 2.31%, significantly higher than the national median of 1.02%.
Median Williamson County home value: $92,430
Median annual Williamson County tax bill: $1,966, lower than the national median property tax bill of $2,400.
How are property taxes in Williamson County calculated?
Property taxes in Williamson County are calculated based on the tax assessed value, which is often lower than the actual market value due to property tax exemptions such as the homestead or senior exemption.
Understanding Williamson County’s property tax system, exemptions, and reduction opportunities can lead to significant savings. Whether you live in Williamson County or another part of the county, knowing local tax details benefits homeowners and investors.
Last Updated April 13, 2026
Williamson County, Illinois Property Tax Bill Calculator
$100,000
$1,500,000
$3,000,000
Median Effective Tax Rate
2.31%
Estimate Property Tax Bill
$2,135
$1,981
How Does the Williamson County Property Tax Calculator Work?
Use this Williamson County property tax calculator to estimate your annual property tax bill. Enter your property's assessed value and our calculator applies Williamson County's median effective tax rate of 2.31% to generate your estimate.
Enter your property's estimated assessed value — the figure the assessment district assigns for tax purposes, which is typically lower than market value after applicable exemptions. Our calculator uses the median effective rate for a more accurate estimate than the statutory millage rate alone.
Your actual bill may vary based on your specific exemptions, local school district levies, and any special assessment districts that apply to your property. Williamson County's median tax rate is lower than the Illinois median tax rate of 2.33%, but the county's median tax bill of $1,966 is $434 lower than the state median tax bill of $2,400.
For a more precise estimate, scroll down to explore city and ZIP code-level tax rate trends across Williamson County.
Property Tax Rates Across Williamson County, Illinois
What Are Effective Property Tax Rates Across Williamson County?
Local government entities set tax rates, which vary widely across Williamson County. Each year, the county estimates its budget for public services and divides that total by the assessed value of all taxable property within its jurisdiction.
Below, compare Williamson County's effective property tax rate to other counties in Illinois or the U.S. median of 1.02%.
Williamson County's median effective rate stands at 2.31%, which is higher than the national median of 1.02%. Within Williamson County, the highest rate is found in Makanda at 2.62%, while West Frankfort has the lowest at 1.86%.
These variations reflect differences in local school district levies, Special service areas (SSAs) assessments, and special district bonds — which compound the base county rate.
Our median effective property tax rate (tax bill ÷ assessor's market value) accounts for exemptions and deductions, making it more accurate than the general median tax rate, which is the midpoint of statutory rates before adjustments.
Median Effective Williamson County Tax Rate
2.31%
Our median effective property tax rate (tax bill ÷ assessor's market value) accounts for exemptions and deductions, making it more accurate than the general median tax rate, which is the midpoint of statutory rates before adjustments.
Median Effective Illinois Tax Rate
2.33%
Median Effective United States Tax Rate
1.02%
Property Tax Rates Across Williamson County, Illinois
| City | 10th Percentile | 25th Percentile | Median Tax Rate | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| Cambria | 0.91% | 1.63% | 2.27% | 2.54% | 2.54% |
| Carbondale | 1.52% | 2.10% | 2.42% | 2.55% | 2.71% |
| Carrier Mills | 1.71% | 2.10% | 2.31% | 2.57% | 2.60% |
| Carterville | 1.53% | 2.02% | 2.25% | 2.42% | 2.52% |
| Colp | 0.68% | 1.45% | 2.24% | 2.28% | 2.28% |
| Creal Springs | 1.45% | 2.07% | 2.50% | 2.73% | 3.45% |
| De Soto | 1.13% | 1.63% | 2.28% | 2.38% | 2.38% |
| Energy | 1.20% | 1.75% | 2.17% | 2.47% | 2.47% |
| Freeman Spur | 0.76% | 1.31% | 2.01% | 2.51% | 2.51% |
| Goreville | 1.36% | 2.06% | 2.54% | 2.73% | 2.73% |
| Herrin | 1.38% | 2.07% | 2.57% | 2.90% | 2.90% |
| Hurst | 0.84% | 1.42% | 2.23% | 2.43% | 2.43% |
| Johnston City | 1.01% | 1.66% | 2.09% | 2.72% | 2.72% |
| Makanda | 1.80% | 2.17% | 2.62% | 3.11% | 3.11% |
| Marion | 1.48% | 1.99% | 2.34% | 2.58% | 2.58% |
| Pittsburg | 1.01% | 1.68% | 2.15% | 2.55% | 2.73% |
| Stonefort | 1.19% | 1.73% | 2.31% | 2.63% | 2.80% |
| Thompsonville | 1.34% | 1.76% | 2.21% | 2.28% | 2.29% |
| West Frankfort | 1.11% | 1.56% | 1.86% | 2.22% | 2.23% |
| Galatia | N/A | N/A | N/A | N/A | N/A |
| New Burnside | N/A | N/A | N/A | N/A | N/A |
Source: Ownwell
Property Tax Assessment Values Across Williamson County, Illinois
When examining property taxes in Williamson County, understanding the distinction between "market value" and "assessed value" is crucial.
The market value is what a willing buyer would pay to a willing seller in an open and competitive market, often influenced by location, property condition, and economic market trends. The Williamson County appraisal district estimates the market value for tax purposes.
The assessed value is the market value minus any applicable exemptions or limits determined by local laws and offerings. The tax assessed value is the figure used to calculate your property taxes or the amount multiplied by your tax rate to get your tax bill.
Assessment notices:
In Williamson County, assessment notices are sent in the spring each year. They'll typically reach your mailbox by the middle of May.
Each property owner receives an assessment notice that contains both the market value and assessed value, along with an estimate of your property tax bill. By providing insights into how assessed and market values are determined, this section helps property owners navigate their tax responsibilities and understand the valuation processes affecting their property taxes in Williamson County.
For example, the median tax bill in Williamson County is $1,966, with tax bills ranging significantly across the county. Carterville has the highest median home price at $139,650.
Property Tax Assessment Values Across Williamson County, Illinois
Source: Ownwell
$28,710
$84,180
$139,650
Median Williamson County Market Value
$92,430
Median Illinois Market Value
$227,888
Median United States Market Value
$235,294
Property Tax Assessment Values Across Williamson County, Illinois
| City | 10th Percentile | 25th Percentile | Median Home Price | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| Cambria | $5,388 | $28,898 | $56,430 | $91,688 | $169,677 |
| Carbondale | $5,772 | $29,670 | $92,295 | $187,148 | $282,297 |
| Carrier Mills | $16,818 | $33,045 | $95,925 | $173,779 | $235,629 |
| Carterville | $38,676 | $78,390 | $139,650 | $221,670 | $311,046 |
| Colp | $3,240 | $7,470 | $28,710 | $54,885 | $90,132 |
| Creal Springs | $16,542 | $39,664 | $89,490 | $170,152 | $239,733 |
| De Soto | $5,514 | $19,020 | $39,090 | $80,160 | $147,882 |
| Energy | $28,311 | $69,758 | $107,430 | $150,360 | $209,640 |
| Freeman Spur | $4,866 | $17,940 | $35,700 | $62,085 | $98,004 |
| Goreville | $12,552 | $33,780 | $88,680 | $127,530 | $222,714 |
| Herrin | $28,950 | $50,910 | $79,350 | $137,220 | $203,916 |
| Hurst | $4,638 | $24,390 | $41,580 | $60,780 | $90,078 |
| Johnston City | $16,707 | $39,352 | $61,395 | $106,680 | $166,731 |
| Makanda | $9,150 | $35,220 | $66,450 | $106,380 | $144,900 |
| Marion | $30,906 | $60,420 | $106,635 | $184,928 | $269,760 |
| Pittsburg | $13,278 | $35,670 | $68,700 | $121,140 | $182,274 |
| Stonefort | $16,446 | $28,148 | $54,330 | $96,690 | $158,276 |
| Thompsonville | $12,344 | $33,484 | $70,238 | $119,149 | $162,567 |
| West Frankfort | $19,521 | $58,684 | $110,040 | $176,198 | $254,316 |
| Galatia | N/A | N/A | N/A | N/A | N/A |
| New Burnside | N/A | N/A | N/A | N/A | N/A |
Source: Ownwell
Property Tax Bills Across Williamson County, Illinois
Property tax bills in Williamson County are based on the assessed value of a home, not its market price. Local tax rates are then applied to that assessment to determine the final bill, so two homes with similar market values can still owe different amounts if their assessed values or taxing jurisdictions differ.
Several factors affect what homeowners pay, including the home’s assessment, local levies, and any exemptions that may reduce taxable value. With a median home price of $92,430, the typical tax burden can vary widely across the county. The 25th percentile tax bill is $997, while the 75th percentile tax bill is $3,751 and the 90th percentile reaches $6,004.
That spread means property taxes can take a meaningful bite out of household budgets, especially for owners whose assessments rise faster than their income. In Williamson County, the highest median tax bill is $2,946 in Carterville, while the lowest is $380 in Colp.
Median Williamson County Tax Bill
$1,966
Median Illinois Tax Bill
$5,277
Median United States Tax Bill
$2,400
Property Tax Bills Across Williamson County, Illinois
| City | 10th Percentile | 25th Percentile | Median Tax Bill | 75th Percentile | 90th Percentile |
|---|---|---|---|---|---|
| Cambria | $127 | $417 | $1,007 | $1,965 | $3,586 |
| Carbondale | $110 | $639 | $2,002 | $4,166 | $6,523 |
| Carrier Mills | $422 | $832 | $1,937 | $4,145 | $5,095 |
| Carterville | $657 | $1,546 | $2,946 | $5,019 | $7,192 |
| Colp | $60 | $124 | $380 | $976 | $1,768 |
| Creal Springs | $309 | $835 | $1,911 | $4,036 | $5,977 |
| De Soto | $106 | $279 | $778 | $1,502 | $2,895 |
| Energy | $449 | $1,183 | $2,109 | $3,279 | $5,021 |
| Freeman Spur | $90 | $225 | $590 | $1,079 | $2,064 |
| Goreville | $241 | $556 | $1,968 | $3,136 | $6,523 |
| Herrin | $476 | $1,056 | $1,829 | $3,329 | $5,292 |
| Hurst | $84 | $304 | $661 | $1,175 | $1,677 |
| Johnston City | $229 | $634 | $1,249 | $2,163 | $3,487 |
| Makanda | $296 | $756 | $1,573 | $2,701 | $3,840 |
| Marion | $553 | $1,227 | $2,288 | $4,215 | $6,486 |
| Pittsburg | $219 | $625 | $1,302 | $2,445 | $3,993 |
| Stonefort | $189 | $539 | $1,034 | $1,934 | $3,569 |
| Thompsonville | $210 | $564 | $1,208 | $2,372 | $3,369 |
| West Frankfort | $299 | $796 | $1,898 | $3,077 | $4,866 |
| Galatia | N/A | N/A | N/A | N/A | N/A |
| New Burnside | N/A | N/A | N/A | N/A | N/A |
Source: Ownwell
Don't miss the deadline to appeal!
Dates | |
|---|---|
| Appeal Deadline | July 1 |
Links | |
|---|---|
| Williamson Tax Assessor | |
| Website | williamsonil.devnetwedge.com |