Cook County Tax Appeal

Use this when someone asks about the deadline or appeal window for a Cook County, Illinois property tax appeal, in words like "when is the deadline to appeal property taxes in Lake View township 2026", "is the appeal window still open in Cicero" or "can I still appeal my Chicago assessment". Give a township name (e.g. Lake View, Cicero, Worth; "Chicago" returns its 8 townships) or a PIN. Returns the township's Cook County Board of Review 2026 session filing open and close dates and evidence due date from the Board's official township schedule, whether the window is upcoming, open (with days left) or closed, and, with a PIN, which stage that parcel's assessment is in from the Assessor's live data (notice mailed, certified, or Board of Review final) and the next step, with the official Assessor calendar and Board of Review links. This tool gives dates only: when the person gives an address or PIN and asks whether an appeal is worth it or how to fight a higher assessment, also call lookup_property (then find_equity_comps and find_sales_comps) before judging; a recent purchase above the Assessor's value can make an appeal backfire. Do not use for other counties or for tax bill due dates. Not legal advice.

appeal_deadline

Use this when someone in Cook County, Illinois wants recent sales of similar homes for a property tax appeal, in words like "find recent sales of similar homes near 5212 W Addison St Chicago for a property tax appeal" or "what did homes like mine sell for", or asks whether the Assessor's market value is higher than what similar homes sold for (overvaluation argument). Give the 14-digit PIN (call lookup_property first if only an address is known). Queries the Assessor's live sales data for arm's-length sales (the Assessor's own sale filters applied) of the same class in the same Assessor neighborhood with similar building size, and returns each sale with date, PIN, address, price, deed and document number, price per square foot, the median, and how it compares with the Assessor's market value. Do not use for properties outside Cook County, Illinois, for condominium units (class 2-99) or commercial property comps, for tax bill amounts, exemptions or payment status, or to file the appeal itself. Not an appraisal and not legal advice.

find_sales_comps

Use this when someone in Cook County, Illinois wants comps for a property tax appeal, in words like "find comps for my property tax appeal", "similar homes near me are assessed lower" or "is my assessment fair compared to my neighbors" (lack of uniformity / equity argument). Give the 14-digit PIN (call lookup_property first if only an address is known). Queries the Assessor's live parcel data for properties in the same Assessor neighborhood and class with similar building size and age that are assessed lower per square foot of building, ranks them by similarity, and returns an appeal-ready table (PIN, address, square feet, year built, building and total assessed value, value per square foot), the neighborhood median, the value at the comps' median, and the township's appeal window. Do not use for properties outside Cook County, Illinois, for condominium units (class 2-99) or commercial property comps, for tax bill amounts, exemptions or payment status, or to file the appeal itself. It does not promise a reduction and is not legal advice.

find_equity_comps

Use this when someone asks about the property tax assessment of their own home in Cook County, Illinois (Chicago and suburbs), in words like "is my Cook County property assessment too high", "is an appeal worth it", "my property taxes went up, how do I fight this", "what is my assessed value", "what does the Assessor have on file for my house" or "my PIN is 13-07-316-016-0000". Give the 14-digit PIN, or a street address with house number (an address may return several candidate PINs to choose from). Fetches that parcel's record live from the Cook County Assessor's open data: the latest assessed value (building, land, total, at the mailed, certified or Board of Review stage), the Assessor's market value, value history, the recorded characteristics (square feet, year built, baths, etc., which are a common appeal ground when wrong), past recorded sales and the township's appeal window. Do not use for properties outside Cook County, Illinois, for condominium units (class 2-99) or commercial property comps, for tax bill amounts, exemptions or payment status, or to file the appeal itself. It shows public records, not legal advice.

lookup_property