Proviso Township: appeal your 2026 assessment by October 27

Was Proviso Township reassessed in 2026?

Yes. Proviso is in the south and west suburbs, which the Assessor reassesses in 2026. Cook County reassesses each area once every three years, so every owner here gets a Reassessment Notice with the property's characteristics and an updated estimated market value.

How values moved here: for the typical house, the first-pass 2026 assessed value is +19% compared with the final 2025 value (median of 41,592 houses with both values). Our calculation from Cook County open data (Assessed Values), not an official figure. Your own home can differ a lot from the typical one.

The Assessor publishes residential valuation reports for each township it reassesses: Assessor's valuation page for Proviso. A higher value does not mean the bill goes up by the same amount: your bill depends on your share of the total value, exemptions and local levies.

Source: Assessor's calendar.

Proviso Township at a glance

• 47,609 residential (class 2) parcels, including 3,856 condominium units.
• Cities and villages with the most homes: Westchester (7,331), Maywood (6,537), Bellwood (5,866), Melrose Park (4,974), Forest Park (4,934), La Grange Park (4,377), Brookfield (4,032), Hillside (2,782), Broadview (2,610), Berkeley (1,776), Stone Park (839), Northlake (617).
• Main ZIP codes: 60154, 60153, 60104, 60160, 60130, 60526, 60513, 60162.

Our calculation from Cook County open data (Assessor Parcel Universe), October 5, 2026. Townships, cities and ZIP codes overlap, so the address check is the reliable way to confirm yours.

Appeals in Proviso Township last year

For tax year 2025, 6,983 residential property appeals from Proviso Township were filed at the Board of Review, and 4,282 at the Assessor. Appealing is a routine step for many owners here.

Our count from Cook County open data (Board of Review Appeal Decision History, Assessor Appeals), counted by property, not official figures.

How to file in Proviso Township

1. Confirm your PIN and township. Use the Assessor's address search or our free check below.
2. Check the notice. The Assessor's rule of thumb: if the characteristics on your notice are correct and the estimated market value is within 10% of what you think your home is worth, an appeal is unlikely to change much. Wrong square footage, rooms or other characteristics are a reason to appeal.
3. File online with the Assessor. On the county's online appeal site choose the residential appeal (or "Residential with Comparable Grid" if you argue lack of uniformity). The Assessor says filing is free and can take as little as 20 minutes, and that you don't need to hire anyone.
4. Comparables are optional. Assessor analysts review similar homes themselves. You may attach up to 6 comparable PINs from your neighborhood that resemble your home in size and style.
5. Board of Review is a second chance. When the Board opens Proviso, you can file there too (online, free). Individual owners may represent themselves; the Board's decision sets the final county value for the year.

More detail: how to appeal step by step · Assessor or Board of Review · choosing comparables.