CHICAGO (WLS) — In a twist affecting many Chicago homeowners, a recent computer upgrade has led to delays in the issuance of property tax bills. Now, a new study sheds light on a more pressing issue: the city is experiencing its most significant property tax hike in over 30 years, and the I-Team is delving into the details.

One of the alarming findings of this study is the disproportionate impact on communities of color, who are shouldering the brunt of these increased taxes. This development has left many residents reeling from sticker shock as they open their new tax bills.

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The Cook County Treasurer’s Office has been scrutinizing these bills and reports a striking citywide increase, with the median residential bill climbing more than 16%. This surge is attributed to increased city spending coupled with a reduction in the number of commercial spaces contributing to the tax revenue pool.

Maria Pappas, the Cook County Treasurer, points out a significant factor in this equation: the declining value of downtown commercial buildings. Due to higher vacancy rates over the years, these properties are contributing approximately $129 million less this cycle, exacerbating the financial burden on residential taxpayers.

Treasurer Maria Pappas says there has been a sharp drop in the value of downtown commercial buildings, paying about $129 million less this cycle because of higher vacancy rates over the years.

“It went down in a landslide, and it is coming back like a snail, slowly, very slowly and not fast enough to handle the residents who carry the burden,” Pappas said. “Because many went unrented. Many are unrented. The taxes went down. What happened was the residences ended up picking up the bulk of these tax increases.”

Black and brown communities on the South and West sides are the hardest hit. In West Garfield Park, bills soared 133%. North Lawndale saw a 99% spike. And in Englewood, taxes climbed more than 80%.

The treasurer says many of those homes may have been undervalued before the most recent assessment, done every three years.

If you haven’t gotten your bill, you can see it now or pay online. Taxes are due Dec. 15. But if you can’t pay right away, you can set up a payment plan with interest. More information on that is at www.cookcountytreasurer.com.