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Updated 2025 Tax Year

Rock Island County
Property Tax Guide

Everything you need to know about property taxes in Rock Island 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, approximately 2.27% statewide average base rate plus local district additions
1st Due
Jun 1
2nd Due
Sep 1
Exemptions
5+ Available
Section 1

How Property Tax Works

Rock Island County, Illinois operates under a property tax system that funds essential local services including schools, municipalities, townships, and county operations. Property taxes are the primary funding source for public education, emergency services, infrastructure maintenance, and local government operations throughout the county. The county follows Illinois state assessment practices with properties assessed at 33.33% of fair market value for residential properties.

Property tax rates in Rock Island County vary significantly by location due to the overlapping special taxing districts including school districts, municipalities, townships, fire protection districts, and other local authorities. While the statewide average effective rate is approximately 2.27%, actual rates within Rock Island County depend on your specific property location and the combination of taxing districts that serve your area. Property owners should expect effective rates that may range from approximately 2.0% to 3.5% depending on their specific tax district combinations.

The county operates on a tax year basis where taxes are levied in one year and become payable the following year. Tax bills are typically issued in spring with installment payment options available to property owners throughout the year.

Section 2

What Makes Up Your Tax Bill

ComponentEstimated Rate RangeDescription
School Districts1.2% - 2.0%Largest component funding local elementary and high school districts
Municipalities0.3% - 0.8%Cities and villages for local services and infrastructure
County Government0.4% - 0.6%Rock Island County operations, courts, sheriff, assessor
Township0.1% - 0.3%Township road maintenance and general assistance
Community College0.2% - 0.4%Black Hawk College district
Fire Protection0.1% - 0.5%Fire protection districts (where applicable)
Library Districts0.1% - 0.3%Public library funding (where applicable)
TIF DistrictsVariableTax Increment Financing districts (where applicable)

Note: These are estimated ranges for FY 2025-2026. Actual tax rates vary significantly by specific location within Rock Island County based on the combination of taxing districts serving each property. Total 2024 levies included $49.9 million for schools, $34.0 million for county operations, and $16.5 million for TIF districts. Contact the Rock Island County Clerk's office for your specific tax rate based on property location.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Rock Island 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 taxes in Rock Island County are typically triggered by changes in property ownership, new construction, or significant improvements that alter the property's assessed value during the tax year. When these changes occur after the annual assessment has been completed, the county may issue supplemental tax bills to account for the difference in tax liability.

The most common triggers include: property sales that result in reassessment, completion of new construction projects, major renovations or additions, and changes in property use classification. The supplemental tax is calculated by determining the difference between the new assessed value and the previous assessed value, then applying the appropriate tax rate for the remaining portion of the tax year.

For example, if a property is reassessed from $200,000 to $300,000 in assessed value after a major renovation completed in March, and the local tax rate is 2.5%, the supplemental tax would be calculated on the $100,000 increase in assessed value, prorated for the remaining 9 months of the tax year: ($100,000 × 0.025 × 9/12 = $1,875 supplemental tax).

Example Calculation

Example 1: $300,000 Home Value

  • Market Value: $300,000
  • Assessed Value (33.33%): $100,000
  • Less: General Homestead Exemption: -$6,000
  • Net Taxable Value: $94,000
  • Tax Rate (estimated): 2.4%
  • Annual Tax: $2,256
  • Monthly Escrow: $188

Example 2: $600,000 Home Value

  • Market Value: $600,000
  • Assessed Value (33.33%): $200,000
  • Less: General Homestead Exemption: -$6,000
  • Net Taxable Value: $194,000
  • Tax Rate (estimated): 2.6%
  • Annual Tax: $5,044
  • Monthly Escrow: $420

Example 3: $1,000,000 Home Value

  • Market Value: $1,000,000
  • Assessed Value (33.33%): $333,333
  • Less: General Homestead Exemption: -$6,000
  • Net Taxable Value: $327,333
  • Tax Rate (estimated): 2.8%
  • Annual Tax: $9,165
  • Monthly Escrow: $764

Note: The General Homestead Exemption reduces assessed value by up to $6,000 and requires annual application. Additional exemptions may be available for seniors, veterans, or disabled persons but require separate applications with specific deadlines.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Rock Island County require borrowers to maintain an escrow account for property tax payments, especially for loans with less than 20% down payment. The lender collects monthly escrow payments along with your mortgage payment and pays property taxes directly to the county on your behalf when taxes become due.

Lenders typically collect escrow payments based on the previous year's tax bill divided by 12 months, plus a cushion amount. When tax bills are issued each spring, lenders receive the bills and make payments according to the county's installment schedule. For 2024 taxes payable in 2025, the first installment is due June 18, 2025, and the second installment is due August 18, 2025.

Property owners with escrow accounts should review their annual escrow analysis statement to verify accuracy and ensure adequate funds are being collected. If property taxes increase due to reassessment or rate changes, lenders may adjust monthly escrow payments and may require a lump sum payment to cover any shortage. Property owners remain responsible for verifying that taxes are paid correctly and on time, even when using escrow services.

How HonestCasa Helps
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Section 6

Frequently Asked Questions

Q: When are 2024 property taxes due in Rock Island County? A: For 2024 taxes payable in 2025, the first installment is due Wednesday, June 18, 2025, and the second installment is due Monday, August 18, 2025. A final payment option is available until November 18, 2025.

Q: What property tax credits are available and do they require application? A: The General Homestead Exemption reduces assessed value by up to $6,000 and requires annual application. Additional credits may be available for seniors, veterans, persons with disabilities, and veterans with disabilities. All credits require separate applications with specific deadlines - they are not automatic.

Q: How does the Homestead Exemption work? A: The General Homestead Exemption reduces your property's equalized assessed value by up to $6,000, which translates to annual tax savings of approximately $120-210 depending on your local tax rate. This credit requires annual application and is not automatically applied to your property.

Q: When can I pay taxes online? A: Online payments for 2024 taxes become available after May 16, 2025. The county typically offers multiple payment methods including online, mail, and in-person options.

Q: How often are properties reassessed? A: Illinois law requires property reassessment at least every four years, though Rock Island County may conduct more frequent assessments. The county assessor reviews property values annually and may adjust assessments based on market conditions, sales data, and property improvements.

Q: What are the penalties for late tax payments? A: Late payments incur interest and penalties according to Illinois state law. Interest typically accrues monthly on unpaid taxes, and additional penalties may apply for significantly delinquent accounts.

Q: How do I appeal my property assessment? A: Property owners who disagree with their assessment can file an appeal with the Rock Island County Board of Review. Appeals must be filed within specific timeframes, typically 30 days after assessment notices are mailed.

Q: Why do tax rates vary within Rock Island County? A: Tax rates vary based on the combination of special taxing districts serving each property, including different school districts, municipalities, fire protection districts, library districts, and other local authorities. Properties in different areas may have significantly different total tax rates based on these overlapping districts.

Verified Sources

Backed by 10 Official Government Sources

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

01
Tax Doc
Where Your Property Taxes Gorockislandcountyil.gov
02
ROCK ISLAND TOWNSHIP, ILLINOIS ANNUAL ...rockislandtownshipil.gov
03
Frequently Asked Questions about the 2024 (Payable 2025 ...rockislandcountyil.gov
04
County
Paying by Mail | Rock Island County, ILrockislandcountyil.gov
05
County
News Flash • Rock Island County, ILrockislandcountyil.gov
06
County
Paying Online | Rock Island County, ILrockislandcountyil.gov
07
County
Assessment Office | Rock Island County, ILrockislandcountyil.gov
08
Owner Occupied Exemptionrockislandcountyil.gov
09
County
What We Do | Rock Island County, ILrockislandcountyil.gov
10
financial reportrockislandcountyil.gov
All sources verified as of 2025 Tax Year

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