Oak Park homeowners can get help challenging their property tax assessments at a free information session Thursday, Aug. 27, at 6:30 p.m. at Beye Elementary School, 230 N. Cuyler Ave., according to an announcement on X.

The session arrives as Cook County's 2025 property tax bills are set to go out by Aug. 31, after a delay from July. Payments are due Oct. 1.

Countywide, the total property tax bill topped $19.9 billion for the 2025 tax year, a 3.9% increase and the 32nd consecutive annual rise, according to the Chicago Tribune. Residential bills jumped 5.34% between the 2024 and 2025 tax years, the Chicago Sun-Times reported, citing Cook County Treasurer Maria Pappas' office.

Pappas said in her office's Aug. 24 analysis that local governments need to do more with less in precarious economic times.

Oak Park Township homeowners received 2026 reassessment notices from the Cook County Assessor on May 6. The assessor's median estimated market value for single-family homes in the township is $559,000, down from $596,000 in 2025 median sales prices, according to the assessor's office. Condo values edged up slightly, from $200,000 to $204,000. Small apartment buildings dropped from $615,000 to $594,000.

Those new valuations will be reflected on 2027 tax bills.

The assessor's appeal deadline for Oak Park Township passed June 18. A separate process through the Cook County Board of Review is now open, with prefiling available for 2026 tax bills, the Sun-Times reported. Appeals can be filed online at no cost, and a lawyer is not required, according to the assessor's office.

Three grounds qualify for an assessor-level appeal: comparable properties assessed differently, an estimated value exceeding what the owner believes the home could sell for, or errors in square footage or classification.

The session is free and open to the public.