Rate Breakdown

Property taxes in Carroll County are calculated by multiplying the assessed value (minus exemptions) by the total local millage rate.

How Property Tax Works in Carroll County

In Carroll County, Illinois, property taxes are the primary source of revenue for schools, roads, public safety, and other local services. The process begins with the County Assessor’s Office evaluating the market value of each parcel every year. Assessments are generally based on recent comparable sales and the annual market value determined on January 1st of the current tax year.

Once the assessor completes the valuation, the millage rates set by various taxing authorities—school district, township, county, and special districts—are applied. A millage rate is one mill, equal to one-tenth of a cent per dollar of assessed value. For example, a 20‑mill rate would translate to $20 of tax for every $1,000 of assessed value. A parcel’s total tax bill is the sum of all applicable millages multiplied by its assessed value.

• Assessments are paid annually, typically due in two installments.
• Assessor’s Office issues the Tax Notice (also known as the Tax Statement) by early June.
• Tax books are filed with the County Clerk’s Office, and audit records are archived for public access.

Available Exemptions

Carroll County residents can reduce their taxable basis through several Illinois exemptions. Applying these exemptions is done at the time the tax notice is mailed; if you are already exempt, you must submit the required documentation to the Assistant County Assessor’s Office.

• Homestead Exemption – Lowers the assessed value of your primary residence by a fixed amount ($50,000 in 2026) or a percentage of the assessed value (up to 3% for properties over $20,000). The exemption applies only to residential real estate.
• Senior Citizen Exemption – For homeowners aged 65 or older (or those defined as disabled under state law) who meet income limits. The exemption amount is $30,000 in 2026, plus an additional $10,000 if the homeowner is disabled.
• Disability and Veteran Exemptions – Disabled voters, retired veterans, and disabled spouses of veterans may qualify for additional tax reductions, ranging from $10,000 to $20,000, depending on eligibility criteria.
• Other Specialized Exemptions – Agricultural, non‑profit, and institutional properties may qualify for further cued exemptions; these require separate applications.

Payment Schedule & Deadlines

Carroll County issues the tax notice around June 1, and the tax year runs from July 1 to June 30. To avoid penalties, pay as follows:

• First installment (50%) – Due by September 15. Retained at the County Treasurer’s Office and can be paid in person, by mail, or electronically via the county’s online portal.
• Second installment (50%) – Due by December 15. Late payments incur a 1% per month penalty, plus interest at the federal rate.
• Installment Flexibility – A taxpayer may request a single installment payment of the full amount by August 31, receiving a 3% discount on the total tax.

Payments received after the due dates will be levied with a late fee of 3% plus 1% month‑by‑month. Unpaid taxes may eventually lead to liens against the property and could trigger foreclosure.

Appealing Your Assessment

If you believe your property’s valuation is too high, you can file an appeal with the Carroll County Assessor’s Office within 30 days of receiving the tax notice.

• Grounds for Appeal – Evidence that sale prices of comparable properties are lower, improvements were not accounted for, or the assessed value exceeds market value.
• Process – Complete the Appeal Form (available online or at the Assessor’s Office), submit supporting documentation, and pay a nominal filing fee ($35). A hearing date will be scheduled.
• Disposition – The Assessor will review the evidence and may reduce the assessed value. If dissatisfied with the decision, an appeal may proceed to the Circuit Court within 60 days of notice of adjustment.
• Best Practices – Keep a detailed inventory of property changes, gather recent appraisal reports, and maintain a record of comparable sales for quick reference.

By understanding how assessments, exemptions, payment schedules, and appeals work in Carroll County, taxpayers can confidently manage their obligations and preserve their property’s value.