Skip to main content
Sign Up For Updates

Why do property value and property taxes increase?

Your property tax bill is based on your property's equalized assessed value and the tax rates, which are determined by tax levy ordinances filed with the respective county after being reduced by PTELL (for non-home rule municipalities and counties) and any applicable tax ceiling rates. If your property taxes increased, a way to determine why they increased is to compare this year's tax bill with last year's tax bill. If the assessed value of your property increased, then you need to contact your chief county assessment officer to find out why your property assessed value increased. If the tax rates shown on your tax bill are higher, contact the county clerk's office. They can explain why the tax rate increased.

Some common reasons property assessments may increase are

  • The property values in your area are increasing.
  • You made improvements to your property (e.g., an addition to your home; extensive remodeling; a new deck, porch, or patio; a new in-ground swimming pool).
  • Your property’s value was too low compared to other properties and this error has been corrected.
  • Your property had a homestead exemption that has been removed.

You will be notified if your property's value changes for a reason other than the chief county assessment officer used a multiplier to bring your property's value to the statutory 33 1/3 percent level. In general assessment years, a list of all property assessments must be printed in a public newspaper published in the county. In the years between general assessments, a list of only those real property assessments that have been changed is published. Taxpayers in counties other than Cook must be mailed notices if their real property assessments change from the preceding year's assessments (unless the change is caused by the chief county assessment officer applying an equalization factor). The notices may be sent to mortgage lenders if arrangements have been made for tax bills to go directly to them; mortgage lenders must mail copies of the notices to their mortgagors, however.

See our General Property Tax Information and Resources web page for more information.

If you have additional inquiries, you may submit them on the Questions, Comments, or Requests form.