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Property tax, explained

How Illinois assessments are built, where they go wrong, and what an owner can actually do about it. 90 articles, written to be useful to somebody who then does it themselves.

AppealsBasicsEvidenceExemptionsIllinoisSituations

What an assessed value actually is It is not a fact the county issued. It is an opinion produced by a model, and opinions can be wrong. Basics · 2 min Assessed value, market value, fair cash value: three different numbers They are related by a ratio set in statute, and confusing them is the most common reason an appeal goes nowhere. Basics · 2 min The 33⅓% rule, and the counties it does not apply to Illinois assesses at one third of fair cash value — except in Cook County, and except for farmland. Basics · 2 min The equalization factor, and why your assessment changed without anyone visiting The state multiplier adjusts a whole county at once. It is not a reassessment, and it is not appealable. Basics · 2 min How your tax bill is actually calculated, step by step Assessment × equalizer − exemptions × tax rate. Only one of those four is yours to argue with. Basics · 2 min Your assessment stayed flat and your bill still went up. Here is why The levy moved, or the base shrank, or an exemption fell off. None of those are visible on your assessment notice. Basics · 2 min The levy: why your appeal does not cost the schools anything Taxing bodies ask for a dollar amount, not a rate. Understanding that changes what an appeal actually does. Basics · 2 min Quadrennial reassessment: the year your number actually gets rebuilt Most of Illinois reassesses every four years. Cook works on a three-year triad. Knowing your year changes your timing. Basics · 2 min Who actually set your value: township assessor, Supervisor of Assessments, or Board of Review Three offices, three different jobs. Sending your argument to the wrong one wastes the only window you get. Basics · 2 min How to read your assessment notice Four numbers and one date matter. The date is the one that ends your options. Basics · 2 min Your property class code, and why it decides who you get compared to The class determines the pool of comparable properties. A wrong class quietly ruins every comparison. Basics · 2 min Uniformity: the argument that does not need an appraisal The Illinois Constitution requires property to be taxed uniformly. That is a ground in its own right. Basics · 2 min Land and building are assessed separately, and only one may be wrong Splitting the assessment splits the argument, and the land half is usually easier to win. Basics · 2 min Your PIN, and how to read it The property index number encodes where your parcel sits. It is also the only identifier that is never ambiguous. Basics · 2 min Why two identical houses end up assessed differently Not corruption. Model drift, stale records, and errors nobody has a reason to find. Basics · 2 min The 30-day rule: the deadline most owners miss Your window opens when the township list is published, not when the notice reaches you. Appeals · 2 min How to file a Board of Review appeal in Illinois The form, the evidence, the copies, and the order to do them in. Appeals · 2 min What actually happens at a Board of Review hearing Ten to fifteen minutes, three people, no robes. Here is the shape of it. Appeals · 2 min Yes, the board can raise your assessment It is uncommon, it is real, and it is the reason to check whether you are the low one first. Appeals · 2 min Do you need a lawyer to appeal your property taxes? For a house, usually not. For a corporate-owned property at PTAB, usually yes. Appeals · 2 min PTAB: what happens after the Board of Review says no A state-level appeal, free to file, slow, and it hears the case fresh. Appeals · 2 min What evidence a board actually accepts Public records beat opinions. Four good comparables beat twenty weak ones. Appeals · 2 min How long an appeal takes, and when you actually see the money Board decisions in weeks to months. The saving shows up on a bill a year later. Appeals · 2 min Should you appeal every year? No. Appeal when something changed, or when you have a case you did not have before. Appeals · 2 min Just bought? Your purchase price is the best evidence you will ever have A recent arm's-length sale of the subject property is the strongest single item in an assessment appeal. Appeals · 2 min How contingency-fee appeal firms work, and when they are worth it They take a share of the first year's saving. That is good value for some properties and poor value for others. Appeals · 2 min Talk to the assessor before you file The cheapest correction is the one that never becomes an appeal. Appeals · 2 min Nine mistakes that sink property tax appeals Most failed appeals fail for the same handful of reasons, and all of them are avoidable. Appeals · 2 min What happens when you win A new assessed value, a lower bill next cycle, and a reduction that usually persists. Appeals · 2 min Appeal or certificate of error: two different remedies One is for disagreement about value. The other is for facts that are simply wrong. Appeals · 2 min How to find comparable properties for a tax appeal Start from the county's own records, not from what you know about the neighbourhood. Evidence · 2 min What makes a comparable good enough to use Similarity on recorded attributes, proximity, and nothing clever. Four tight ones beat twenty loose. Evidence · 2 min Using your county's parcel search like an assessor would Every Illinois county publishes a searchable roll. Most owners never open theirs. Evidence · 2 min Assessed value per square foot: the number that makes comparisons possible Raw assessments cannot be compared. Rates can. Evidence · 2 min Why a Zestimate will not help your appeal Automated values are not accepted as evidence of value, and boards say so out loud. Evidence · 2 min When paying for an appraisal is worth it A few hundred dollars against a multi-year saving — the arithmetic is usually clear either way. Evidence · 2 min Documenting a factual error in your property record The easiest win available, and it needs evidence rather than argument. Evidence · 2 min Where to find recent sales data free County recorder, assessor sales files, and IDOR declarations — no subscription needed. Evidence · 2 min The valuation date: why last month's sale may be the wrong evidence An assessment speaks to a specific date. Evidence has to speak to the same one. Evidence · 2 min Building an evidence packet a board can actually use One page of argument, one table, and the records behind it. In that order. Evidence · 2 min Using photographs as evidence Photographs prove condition and prove absence. Both are worth more than description. Evidence · 2 min Adjusting comparables when nothing matches exactly Small differences can be adjusted for. Large ones mean you picked the wrong comparable. Evidence · 2 min How many comparables you actually need Three to five tight ones. More is not stronger, and it is often weaker. Evidence · 2 min How to read a property record card The county's full description of your house, and the single best place to find a winnable error. Evidence · 2 min Writing the appeal so it is decided in your favour on paper Many appeals never get a hearing. Write as though yours will not. Evidence · 2 min The general homestead exemption, and how it goes missing The one nearly every Illinois owner-occupier gets — and the one that quietly falls off after a title change. Exemptions · 2 min The senior citizens homestead exemption An additional reduction for owner-occupiers aged 65 or over. Some counties renew it automatically; some do not. Exemptions · 2 min The senior assessment freeze: what it does and does not freeze It freezes the assessed value, not the tax bill. People are surprised by that every year. Exemptions · 2 min The home improvement exemption: renovate without an immediate tax rise Up to a statutory limit of added value is exempt for four years. Most people never claim it. Exemptions · 2 min Exemptions for veterans with disabilities Tiered by service-connected disability rating, and at the top tier the property can be fully exempt. Exemptions · 2 min The homestead exemption for persons with disabilities An annual exemption for owner-occupiers with a qualifying disability, requiring yearly proof. Exemptions · 2 min Why your exemption disappeared Title changes, missed renewals, and deaths. All three are fixable, often retroactively. Exemptions · 2 min Check exemptions before you appeal An exemption is a form. An appeal is a hearing with risk. Do the cheap one first. Exemptions · 2 min Where exemptions actually apply in the calculation After equalization, before the rate. The order determines what a given exemption is worth to you. Exemptions · 2 min Applying for and renewing exemptions without losing a year Which renew automatically, which do not, and the calendar that keeps them. Exemptions · 2 min Charitable, religious and educational exemptions Owner status is not enough. Illinois tests actual use, parcel by parcel. Exemptions · 2 min When your property is damaged: disaster relief and reassessment A destroyed or damaged building should not be assessed as though it still stands. Exemptions · 2 min Eight exemption errors worth ten minutes of your time A checklist to run against your tax bill before you consider anything harder. Exemptions · 2 min Renting out your home ends the homestead exemption Occupancy is the test. Moving out without saying so creates a problem that compounds. Exemptions · 2 min What to do about exemptions in your first year of ownership The seller's exemptions do not become yours. Assume nothing carried over. Exemptions · 2 min Cook County: why advice written for Illinois usually does not apply Different ratios, a different cycle, an extra appeal stage and a very large multiplier. Illinois · 2 min Cook County's triennial reassessment and the three triads Your township is reassessed every third year. Knowing which year is yours changes when to act. Illinois · 2 min Cook County's class codes, and what they do to your assessment The class sets the assessment level. It also sets who you are allowed to compare yourself to. Illinois · 2 min The two-stage Cook County appeal: Assessor first, Board of Review second Two separate filings, two separate windows, and losing the first does not end anything. Illinois · 2 min The collar counties: DuPage, Lake, Will, Kane, McHenry Standard Illinois rules, high tax rates, and quadrennial cycles that differ by township. Illinois · 2 min Appealing downstate: smaller offices, same law, less data The rules are identical. What changes is how much is published online. Illinois · 2 min Farmland is not assessed on what it would sell for Illinois assesses farmland on agricultural economic value from soil productivity, not sale price. Illinois · 2 min TIF districts: why your rate can rise while values grow Tax increment financing freezes the base for other taxing bodies and captures the growth. Illinois · 2 min Special service areas: the extra line on your bill A defined area taxed additionally for services only it receives. Check whether yours still exists. Illinois · 2 min Your school district decides most of your bill Schools commonly take the majority of an Illinois property tax bill, which is why identical houses differ. Illinois · 2 min Using Illinois FOIA to get the assessment roll Assessment records are public. Ask for the electronic file, and cite the subsection that requires it. Illinois · 2 min Townships, and why yours matters more than you think The township is the unit of assessment, the unit of the reassessment cycle, and the unit of your deadline. Illinois · 2 min The Illinois property tax calendar, and why you pay a year late Assessed one year, billed the next. Everything about timing follows from that. Illinois · 2 min Tax caps (PTELL): what they limit, and what they do not PTELL limits how fast a taxing body's total levy can grow. It does not cap your individual bill. Illinois · 2 min How new construction gets assessed, and the partial first year A house completed mid-year is assessed for the part of the year it existed. Illinois · 2 min Condominium assessments: your best comparables are in your own building Units in one building share everything except floor, view and finish — which makes the comparison unusually clean. Situations · 2 min Vacant land: assessed on what it could be, not what it is Land assessment follows zoning, buildability and access. Any of those can be wrong on file. Situations · 2 min Rental property: no homestead exemption, every other remedy intact Landlords lose the exemption and keep the appeal. Condition is often the strongest argument. Situations · 2 min Inherited property: exemptions end, and the record is usually stale The exemptions died with the owner. The assessment probably has not been looked at in years. Situations · 2 min Divorce: title changes end exemptions, and both names still owe Removing a spouse from title can drop the homestead exemption without anyone being told. Situations · 2 min Commercial property: income is the argument Commercial assessments turn on income, and the evidence is your own operating statements. Situations · 2 min Mixed-use property: two uses, one parcel, frequent errors A shop below and a flat above are assessed differently, and the split is often stale. Situations · 2 min Busy roads, rail lines and substations: assessing external factors Mass appraisal often misses what is next door. It is a documentable argument. Situations · 2 min Corner lots, flag lots and unusable land Square footage is not usable area. Where the difference is large, the assessment should reflect it. Situations · 2 min Property in a flood zone Floodplain designation affects insurance, buildability and price. It should affect assessment. Situations · 2 min Historic designation: restrictions, and the freeze that offsets them Illinois offers an assessment freeze for rehabilitating a designated historic residence. Situations · 2 min Do solar panels raise your assessment in Illinois? Illinois provides a special valuation for solar energy systems. It has to be claimed. Situations · 2 min Does a home office change your property tax? For most people, no. Where it changes classification, it can matter a great deal. Situations · 2 min Mobile and manufactured homes: two different tax systems Whether it is taxed as real property or under the privilege tax depends on how it sits on the land. Situations · 2 min Owning several parcels: check them together, appeal them separately Assessments are individual. Reviewing a portfolio at once shows you which one is the outlier. Situations · 2 min

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