Researching county assessment records before estimating future taxes
Understand how to access and review Illinois county property assessment records to better estimate potential tax burdens before purchasing a new home.
The short answer
Researching assessment records requires identifying the assessment cycle in your county and locating public records. Since property taxes are determined by equalized assessed value and local taxing district levies, reviewing these records helps you understand the historical assessment basis of a property. Always verify if the records reflect recent changes or exemptions, as tax bills are paid in the year following the assessment.
Locating Assessment Records
Assessment records are public and open for inspection. You can generally find these through your county assessor's office. Start by identifying the parcel index number (PIN) of the property.
Decision Worksheet: List the county name, the website or address of the assessor's office, and the property PIN. Determine if the county provides online portals to view history for the last three years.
Understanding Assessment Cycles
Illinois property tax cycles generally span two years. Taxes paid in the current year relate to the prior year's assessment. Knowing the cycle helps you identify if the current assessment has been updated recently.
Hypothetical Planning: If you are looking at a property in late 2025 or 2026, research if the prior year assessment was finalized. Confirm with the assessor if the assessment is based on 33 1/3 percent of fair market value or 10 percent for Cook County.
Accounting for Exemptions
Assessments are not the final tax bill because of potential exemptions. Owner-occupied residences often qualify for a General Homestead Exemption. Other exemptions exist for seniors, veterans, and individuals with disabilities.
Decision Worksheet: Check if the current owner claims any homestead exemptions. If the current owner is a senior, your future tax bill may be higher if you do not qualify for the same exemptions.
Identifying Assessment Changes
Assessment changes are published in newspapers of general circulation. Outside Cook County, taxpayers receive mailed notices. If you are under contract, check if the seller received a recent change notice.
Decision Worksheet: Ask your real estate professional: 'Has a recent notice of assessment change been issued for this property in the last twelve months?'
Checklist
- Verify the property's PIN with the county assessor.
- Confirm if the county assesses at 33 1/3 percent or 10 percent.
- Check for existing homestead, senior, or veteran exemptions.
- Inquire if the seller received a recent assessment change notice.
- Determine the most recent year's equalized assessed value (EAV).
Common questions
Can I trust the current tax amount as a future indicator?
Not necessarily. Taxes depend on local taxing district levies and the EAV. Changes in exemptions or district levies can alter the tax bill significantly regardless of past payments.
Where can I find assessment records?
Assessment records are public documents maintained by the local government, typically the county assessor or supervisor of assessments office, and are often available on county websites.
Sources
- CFPB — Loan Estimate explainerChecked October 12, 2026
- CFPB — Closing Disclosure explainerChecked October 12, 2026
- Illinois Department of Revenue — Property tax overviewChecked October 12, 2026
- IRS Publication 523 — Selling Your HomeChecked October 12, 2026
This guide is general educational content from SQFT IO, prepared with AI assistance. It is not legal, tax or loan advice. Talk with a licensed attorney, tax professional or lender about your situation. SQFT IO Illinois license 478.027617.