One of the more significant expenses associated with home ownership is property taxes. Yet most homeowners pay their tax bill without checking whether the assessment is accurate. Consider these steps to verify your property tax assessment:
- Understand how your assessment is calculated. Many homeowners look at their assessment, see it is less than the home's market value, and leave it at that. However, most assessments are based on a percentage of full market value. Just because your assessment is less than the home's market value doesn't mean it is correct. If it's not clearly stated on the assessment notice, find out how the assessment is calculated from the assessor.
- Verify your home's information on file at the assessor's office. Make sure all information is accurate, including square footage, number of bedrooms and bathrooms, whether the basement is finished, etc. Also check for clerical errors in any calculations. Verify that any tax breaks you are entitled to are reflected in the records, such a reductions for a owner-occupied home or for the elderly, disabled, or veterans.
- Check values of comparable properties to see whether your assessment is in line. It is best to find comparable properties of a similar size in your own neighborhood, checking at least three to five properties.
- Appeal if you find an inaccurate assessment. Forms are typically available at the assessor's office, but adhere to the deadlines. Most appeals must be filed within a narrow time period. Consider discussing the issue with the assessor first, since it's not unusual for an assessor to correct an error without an appeal.
When to Challenge Your Property Tax Assessment
While many homeowners only glance at their annual assessment, it’s worth taking a closer look in these situations:
- Your home’s market value has declined — especially after a market correction or local downturn.
- You’ve noticed discrepancies in property records (wrong square footage, incorrect number of bedrooms, etc.).
- Nearby similar homes are assessed lower — and you’re paying significantly more in taxes.
- You recently purchased your home for less than the assessed value.
- You qualify for exemptions (e.g., the General Homestead Exemption, Senior Citizens Homestead Exemption, or Disabled Veterans Exemption) but don’t see them applied.
Tip: Mark your calendar! Appeals usually have a limited window — often just 30 to 60 days from the notice date. Missing the deadline could cost you a year of potential savings.
Important for Illinois Residents
- Each county has its own Board of Review and appeals calendar. You typically have 30 days from the date your assessment notice is mailed to file an appeal.
- You can often begin by informally contacting your township assessor to resolve minor discrepancies before initiating a formal appeal.
Tip: To check comparable property values and appeal deadlines, visit your county assessor's website or contact the Illinois Department of Revenue for resources.