Cook County property tax
Proviso Township property tax appeal guide
Your township: Proviso
Cook County Assessor
Deadline: October 27, 2026 · 38 days remaining Official Cook County Assessor source ↗
Board of Review
Current dates are not verified here. Check the official source. Official Board of Review source ↗
Proviso Township's Assessor appeal window is open now through October 27, 2026.
File with the Cook County Assessor · $0 filing fee ↗County calendar updated September 15, 2026.
Proviso Township contains multiple municipalities, but its assessment schedule is tied to the township rather than an owner's municipality. Proviso was reassessed with the South Triad for 2026 and is next scheduled for 2029. The Board of Review opens a filing window for the township every year, including years between reassessments.
Recent home sales in Proviso Township
From July 13, 2024 through July 13, 2026, the comparison pool contains 2,485 recorded single-family sales.
- Median sale price: $330,000
- Median sale price per square foot: $249
- Median building size: 1,242 square feet
These are recorded single-family sales used as comparison evidence, not an estimate of any home's value.
Evidence to review
- Audit the Assessor's class and building characteristics before relying on the record as the foundation for an appeal.
- When similar subdivision houses are available, compare their original floor plans as well as additions, finished space, and present condition.
- Use recorded sales from the same assessment neighborhood and explain any meaningful difference in lot area or accessory structures.
- Date photographs of defects or deferred work and identify where each pictured condition appears on the property.
Official sources
Cook County Assessor calendar · Cook County Board of Review appeals
You file directly with Cook County for free. We provide optional research, not representation or guaranteed savings.
Editorial guidance reviewed 2026-09-19. Filing dates are checked separately.