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Updated 2025 Tax Year

Stephenson County
Property Tax Guide

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

10 Official Sources
8 min read
Quick Facts
Tax Rate
Varies by taxing districts, approximately 2.27% base rate plus local district additions
1st Due
Jun 1
2nd Due
Sep 1
Exemptions
5+ Available
Section 1

How Property Tax Works

Stephenson County, Illinois operates under Illinois' property tax system, which funds essential local services including schools, fire protection, libraries, parks, and county operations. Property taxes are calculated based on your property's assessed value multiplied by the total tax rate for your specific location within the county. Illinois has a statewide average effective tax rate of approximately 2.27%, though actual rates in Stephenson County vary significantly depending on your property's location and the special taxing districts that serve your area.

Your actual property tax rate depends on which combination of taxing districts serve your property, including school districts, municipalities, townships, fire protection districts, library districts, and other special service areas. This means two properties with identical assessed values can have different tax bills based on their location within Stephenson County. The county uses an equalized assessed value (EAV) system where residential properties are assessed at 33.33% of fair market value, and various tax credits and exemptions may be available to qualifying property owners, though most require annual applications.

Section 2

What Makes Up Your Tax Bill

ComponentEstimated Rate RangeDescription
County General0.3% - 0.5%County operations, courts, sheriff, health services
School Districts1.2% - 1.8%Elementary and high school districts vary by location
Township0.1% - 0.3%Township road maintenance and general services
Municipality0.2% - 0.6%City/village services (if within incorporated area)
Fire Protection0.1% - 0.4%Fire department services and equipment
Library District0.1% - 0.2%Public library operations
Other Special Districts0.1% - 0.3%Parks, mosquito abatement, other special services
Total Estimated Range2.1% - 4.1%Varies significantly by location within county

Note: The 2025 levy year tax rates are not yet finalized as of early 2025. Final rates will be determined after all taxing districts set their levies. Check the Stephenson County Clerk's office or visit stephensonil.devnetwedge.com for current rates applicable to your specific property address.

Section 3

When Are Property Taxes Due?

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

First Installment
Jun 1
Delinquent after Dec 10
Second Installment
Sep 1
Delinquent after Apr 10
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

Supplemental property taxes in Stephenson County are additional tax bills issued when there are changes to property ownership, new construction, or improvements that increase a property's assessed value during the tax year. These situations trigger a recalculation of taxes based on the updated assessment. The supplemental tax represents the difference between what was originally billed and what should have been billed based on the new assessment.

For example, if you complete a home addition worth $50,000 in August, and your property was previously assessed at $200,000, the county assessor will add the improvement's assessed value (typically $16,665 at the 33.33% assessment ratio) to your property's total assessed value. You'll receive a supplemental tax bill for the additional taxes owed on that $16,665 increase, prorated for the portion of the tax year remaining after the improvement was completed.

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (33.33%): $100,000
  • Homeowner Exemption Applied: -$10,000 (requires application)
  • Net Taxable EAV: $90,000
  • Estimated Tax Rate: 2.5%
  • Annual Tax: $2,250
  • Monthly Escrow: $187.50

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (33.33%): $200,000
  • Homeowner Exemption Applied: -$10,000 (requires application)
  • Net Taxable EAV: $190,000
  • Estimated Tax Rate: 2.8%
  • Annual Tax: $5,320
  • Monthly Escrow: $443.33

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (33.33%): $333,333
  • Homeowner Exemption Applied: -$10,000 (requires application)
  • Net Taxable EAV: $323,333
  • Estimated Tax Rate: 3.2%
  • Annual Tax: $10,347
  • Monthly Escrow: $862.25

Note: All exemptions and credits require annual applications and are not automatically applied. Tax rates vary by specific location and taxing districts.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Stephenson County require borrowers to maintain an escrow account for property tax payments, particularly for loans with less than 20% down payment. Your lender will estimate your annual property tax bill and divide it by 12 to determine your monthly escrow payment. The lender typically collects 2-3 months of additional taxes at closing to ensure sufficient funds are available when tax bills are due.

Stephenson County property tax bills are mailed in mid-May, with the first installment due June 27 and the second installment due September 5. Your mortgage servicer will pay these bills directly from your escrow account. Lenders are required to provide an annual escrow analysis showing how your funds were used and whether adjustments to your monthly payment are needed. If your actual tax bill differs significantly from the estimate, your monthly escrow payment may increase or decrease, and you may owe additional funds or receive a refund.

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 property taxes due in Stephenson County for 2025? A: Property tax bills are mailed May 16, 2025. The first installment is due June 27, 2025, and the second installment is due September 5, 2025. The final payment deadline is November 4, 2025. A 1.5% monthly penalty begins accruing on unpaid amounts starting June 28 for the first installment.

Q: What tax credits are available and do they require applications? A: The primary tax credit is the Homeowner Exemption, which reduces your equalized assessed value by up to $10,000. This requires an annual application. The Returning Veteran's Homestead Exemption provides a $5,000 EAV reduction for qualifying veterans and also requires application with income documentation.

Q: How does the Homestead Exemption work? A: The Homestead Exemption is actually the Homeowner Exemption in Illinois, which reduces your property's equalized assessed value by up to $10,000. This is not automatic - you must apply annually. It does not cap assessment increases but provides a direct reduction in the taxable value used to calculate your bill.

Q: How often are properties reassessed in Stephenson County? A: Illinois law requires properties to be reassessed at least every four years, though counties may reassess more frequently. Stephenson County follows the state schedule for general reassessments, with annual updates for new construction and property improvements.

Q: What happens if I pay my taxes late? A: Late payments incur a 1.5% monthly penalty that compounds each month. After June 27, unpaid first installments accrue penalties, increasing by an additional 1.5% each subsequent month. Severely delinquent taxes can eventually result in tax sale proceedings.

Q: Can I pay my property taxes online? A: Yes, Stephenson County offers online payment options. You can pay online at stephensonil.devnetwedge.com from May 19 through November 4. The county encourages contactless payment methods.

Q: How do I appeal my property assessment? A: Property assessment appeals must be filed with the Stephenson County Board of Review, typically within 30 days of receiving your assessment notice. You'll need evidence supporting your claim that the assessed value is incorrect, such as recent appraisals or comparable sales data.

Q: Why might my tax bill change from year to year? A: Your tax bill can change due to reassessment of your property's value, changes in tax rates set by various taxing districts, loss of exemptions, property improvements, or changes in the overall tax base within your taxing districts.

Q: What special districts might affect my tax rate? A: Depending on your location in Stephenson County, you may be subject to taxes from school districts, fire protection districts, library districts, park districts, mosquito abatement districts, and municipal taxes if you live within an incorporated city or village. Each adds to your total tax rate.

Q: Where can I find the specific tax rate for my property? A: Contact the Stephenson County Clerk's office or search online at stephensonil.devnetwedge.com using your property address or PIN number to find the exact combination of taxing districts and rates that apply to your specific property.

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