Mar 4, 2024 - News

How Cook County is trying to fix inaccurate property tax data

Illustration of a welcome mat that is a one-hundred dollar bill.

Illustration: Maura Losch/Axios

Last May I investigated why my property taxes jumped by more than 70% and learned the increase was driven by inaccurate data at the Cook County Assessor's Office (CCAO).

Why it matters: These tax hikes, based on outdated county records, have hit others, too, including a third-generation garden business in Palatine that recently had to close because of bad assessor data.

The latest: As homeowners pay their property taxes this month, we're checking in to see what the CCAO has done to improve the quality of its records so fewer people are stuck paying erroneously high bills.

Catch up quick: After discovering they wrongly assessed my home based on inaccurate "comp" data, CCAO officials said they would process a "certificate of error."

  • That process took more than 10 months and required me to pay thousands in extra taxes.
  • Last month the county finally refunded my overpayments, and this month I started paying taxes based on better data.

But did it have to take that long?

What they're saying: "The [correction] process involves multiple Cook County offices and operates in accordance with the countywide property tax timeline," a spokesperson tells Axios.

  • CCAO officials have not responded to Axios questions about whether my wait was unusual and how long the process typically takes.

State of play: The office told Axios in May they'd work on four steps to improve the quality of their records.

Here's the progress they report today:

  • Better methods of obtaining new construction records through timely sharing of permit data.
  • A new "sales validation" team tasked with reviewing unusually priced properties will launch "in the second quarter of this year."
  • New budgeting for four more field inspectors (a 25% increase) who can actually visit properties to verify and correct CCAO data. Three have already been hired.
  • Some new access to federal appraisal data, although the office says it still needs more "for assessors around the country to help reduce property tax inequity."

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