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Updated 2025 Tax Year

Union County
Property Tax Guide

Everything you need to know about property taxes in Union County, IL. Rates, due dates, exemptions, and how it affects your monthly payment.

10 Official Sources
8 min read
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Quick Facts
Tax Rate
Varies by district due to overlapping taxing bodies - contact county assessor for specific rate
Exemptions
4+ Available
Section 1

How Property Tax Works

Union County, Illinois operates under a property tax system that funds essential local services including schools, municipal operations, fire protection, libraries, and county government functions. Property taxes are calculated based on the Equalized Assessed Value (EAV) of your property, which is approximately 33.33% of fair market value for residential properties. The Illinois Property Tax Extension Limitation Law (PTELL), effective in Union County since 1997, limits the annual growth of property tax extensions.

Property tax rates in Union County vary significantly by location due to overlapping special taxing districts such as school districts, municipalities, townships, fire protection districts, and library districts. While Illinois has a statewide average effective rate of approximately 2.27%, your actual rate in Union County will depend on which specific taxing districts serve your property. Tax bills are typically issued twice per year with installments due June 1st and September 1st, though exact dates may vary.

Section 2

What Makes Up Your Tax Bill

Note: 2025 property tax rates are not yet available. The following represents typical taxing district components that make up your total rate. Rates vary by specific location within Union County based on which districts serve your property.

ComponentTypical Rate RangeDescription
County General0.3% - 0.6%County operations, sheriff, courts, health services
School Districts4.0% - 7.0%Elementary and high school districts (varies significantly)
Township0.1% - 0.3%Road maintenance, general assistance
Municipality0.5% - 1.2%City/village services (if within municipal boundaries)
Fire Protection0.2% - 0.5%Fire districts and emergency services
Library District0.1% - 0.3%Public library services
Other Districts0.1% - 0.4%Parks, drainage, cemetery districts as applicable

Total Effective Rate Range: 5.3% - 10.3% (varies by specific property location and applicable districts)

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Union County, property taxes are due in two installments:

Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Union County does not typically issue supplemental tax bills like some other Illinois counties. However, property tax adjustments may occur through the standard assessment and appeal process. Changes in assessed value due to new construction, improvements, or successful appeals are generally reflected in the following year's regular tax bill rather than through supplemental assessments.

Under PTELL, taxing districts in Union County are limited in how much they can increase their total levy each year, which helps control overall tax growth. If your property's assessed value increases significantly due to improvements or market changes, your individual tax burden may still rise even with PTELL limitations in place.

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (33.33%): $100,000
  • Less: General Homestead Exemption: -$10,000
  • Equalized Assessed Value: $90,000
  • Tax Rate (estimated 6.5%): × 0.065
  • Annual Tax: $5,850
  • Monthly Escrow: $487.50

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (33.33%): $200,000
  • Less: General Homestead Exemption: -$10,000
  • Equalized Assessed Value: $190,000
  • Tax Rate (estimated 7.2%): × 0.072
  • Annual Tax: $13,680
  • Monthly Escrow: $1,140

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (33.33%): $333,333
  • Less: General Homestead Exemption: -$10,000
  • Equalized Assessed Value: $323,333
  • Tax Rate (estimated 8.0%): × 0.080
  • Annual Tax: $25,867
  • Monthly Escrow: $2,156

Note: Homestead and other exemptions require application and are not automatic.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Union County require property tax escrow accounts for borrowers with less than 20% down payment. Your lender will collect approximately 1/12th of your annual property tax bill with each monthly mortgage payment, plus an initial cushion of 2-3 months. The escrow account pays your property taxes directly to Union County when they become due.

Lenders typically conduct annual escrow analyses and may adjust your monthly payment if tax amounts change significantly. You'll receive an escrow statement showing deposits, payments made, and any surplus or shortage. Since Union County taxes are due June 1st and September 1st, your lender will make payments accordingly. Property owners should verify that payments are made timely, as you remain ultimately responsible for ensuring taxes are paid even when using escrow.

How HonestCasa Helps
  • Understand whether your escrow is set correctly
  • See how rising taxes will change your monthly payment
  • Plan ahead instead of being surprised by "shortage" letters
Section 6

Frequently Asked Questions

Q: When are Union County property taxes due? A: Property taxes are due in two installments: June 1st and September 1st. However, exact dates may vary slightly each year. If tax bills are mailed late, the first installment deadline extends to 30 days after the bill date.

Q: What property tax credits are available and do I need to apply? A: The main credit is the General Homestead Exemption, which reduces your Equalized Assessed Value by up to $10,000. You must own and occupy the property as your primary residence as of January 1st and APPLICATION IS REQUIRED - it is not automatic. Senior Citizens (65+) may qualify for additional exemptions.

Q: How does the Homestead Exemption work? A: The Homestead Exemption reduces your property's Equalized Assessed Value by up to $10,000, not the market value. For seniors, there's also a Senior Citizens Assessment Freeze that can limit assessment increases. Both require annual application and qualifying as of January 1st of the assessment year.

Q: What are the penalties for late payment? A: Unpaid taxes accrue penalties at 1.5% per month (1% for agricultural property) from the due date. There's also a $10 penalty fee for payments made after January 15th in addition to interest charges.

Q: How often are properties reassessed? A: Illinois law requires properties to be reassessed at least every four years, though Union County may reassess more frequently. Assessment notices are typically mailed in late spring or early summer.

Q: Can I appeal my property assessment? A: Yes, you can appeal to the Union County Board of Review if you believe your assessment is incorrect. Appeals must typically be filed by the deadline shown on your assessment notice, usually within 30 days.

Q: Can I pay my property taxes online? A: Contact the Union County Treasurer's office directly for current online payment options and accepted methods. Many Illinois counties now offer online payment systems for convenience.

Q: Why do property tax rates vary within Union County? A: Your total tax rate depends on which taxing districts serve your specific property location. Two properties of equal value can have different tax bills based on their school district, fire district, library district, and whether they're within municipal boundaries.

Verified Sources

Backed by 10 Official Government Sources

Every fact in this guide is sourced from official county, state, and federal documents.

01
County
Union County Illinoisunioncountyil.gov
02
County
union county governmentunioncountyil.gov
03
County
Union County Illinoisunioncountyil.gov
04
When Is the last day to pay?lakecountyil.gov
05
County
Union County Treasurerunioncountyiowa.gov
06
Tax Doc
When do I have to pay my property taxes?tax.illinois.gov
07
homestead exemption noticeunioncountyil.gov
08
Quit Claim Deed-Statutory Form.unioncountyil.gov
09
Tax Doc
PTAX-1-A, Introduction to Residential Assessment Practicestax.illinois.gov
10
County
union county governmentunioncountyil.gov
All sources verified as of 2025 Tax Year

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