Class 3 tax planning stopped being optional the day the 2024 Chicago reassessment landed. Per the Cook County Assessor’s final data, Class 3 multifamily assessed values rose 34% citywide. That was one of the two largest jumps of any class. Only industrial rose faster. For an apartment owner, that is not an abstraction. The assessment is the base of the bill. So a bigger base means a bigger check unless the value gets challenged with evidence. Here is what the data actually says, and what to do about it.
- How the 34% Class 3 jump compares to every other class, with the source.
- Why mass-model assessments outrun real rent rolls, and how appeals exploit that.
- The planning calendar that runs from township windows to the 2027 reassessment.
What the 2024 Numbers Actually Show
Start with definitions. Per the Assessor’s classification rules, Class 3 covers larger multifamily rental buildings, the family that starts at seven units. Also, as residential property it assesses at 10% of market value. Now the growth table, straight from the Assessor’s final 2024 Chicago reassessment data. Class 2 residential rose 18%. Class 5A commercial, the offices and hotels and retail, rose 22%. Class 3 multifamily rose 34%. Class 5B industrial rose 65%. So apartments carried one of the two heaviest increases in the city, and the release says exactly that.
Put the 34% on one building to feel it. Say a 24-unit property carried a $400,000 assessed value into the cycle. A 34% increase moves it to $536,000 before anyone checks the rent roll. Then the equalizer and the local rate multiply the difference on every bill that follows. For example, an owner who shrugs at the spring notice meets that number again each year until an appeal resets it. The planning starts at the notice, not at the bill.
One honest note on geography. Still, township-level swings vary a lot. The Assessor publishes those details on its reassessment data pages rather than in the release. If a specific neighborhood number matters to your planning, pull it from the dashboard instead of trusting a blog’s recollection, ours included.
Why Assessments Outrun Rent Rolls
Mass assessment prices thousands of buildings with models. Then the models run on assumptions: stabilized occupancy, market rents, typical expenses. Still, a real building is rarely that tidy. For example, maybe two units sat vacant through a renovation. Maybe the rent roll carries long-term tenants below market, or the insurance bill doubled. Meanwhile, the model does not know any of that. So the assessment can describe an idealized version of the property. Then the owner pays taxes on a building that does not exist.
So that gap is exactly what appeals are for. The challenge is not an argument about fairness. It is a documentation exercise: actual income against assumed income, actual expenses against typical ones.
Class 3 Tax Planning Runs on Building Evidence
Instead, the winning file for a multifamily appeal looks like underwriting. Rent rolls with real occupancy history. Concessions and collection losses, documented. Operating expenses with the ugly line items included. Then the income approach turns those inputs into a supportable value, which is the analysis review bodies actually test. We broke down how that works in our piece on NOI and cap rates under scrutiny. Also, the full process lives in our commercial tax appeal guide. For owners with several buildings, a preliminary review sorts the portfolio first. So the full workup goes only where the gap justifies it.
Meanwhile, affordable housing owners have an extra layer. Class 9 properties and LIHTC projects carry their own filings and their own rules. So incentive paperwork and appeal strategy need to move together. The Assessor’s published forms are the starting point, and counsel should see both tracks at once.
The Calendar Does the Compounding
Appeal windows open township by township every year, first at the Assessor and then at the Board of Review. So a 34% jump left unchallenged does not cost you once. It compounds through every bill until a successful appeal resets the number. Meanwhile, the next citywide reassessment arrives in 2027 under the triennial cycle, and the appeal volume records keep climbing, as we covered in the BOR data breakdown. Owners who build the evidence file now use it twice: this cycle’s appeal and the 2027 response.
Plan From the Rent Roll, Not the Notice
The 2024 numbers made one thing plain. Multifamily is carrying a heavy share of Chicago’s assessment growth. Meanwhile, the owners who absorb it quietly subsidize the ones who challenge it. So run the planning sequence in order. Pull the actual performance data and compare it to what the assessment implies. Then screen the gap, and file in the window with a value someone can defend in the room. The building’s real numbers are the whole strategy.
Is your building taxed on rents it never collected?
Get a valuation built on your actual income story, ready for the hearing that tests it.
Frequently Asked Questions
How much did Class 3 assessments rise in the 2024 reassessment?
Per the Cook County Assessor’s final data, Class 3 multifamily assessed values rose 34% citywide. That was one of the two largest increases of any class, alongside Class 5B industrial at 65%. Class 2 residential rose 18% and Class 5A commercial rose 22%.
What counts as a Class 3 property?
The Class 3 family covers larger multifamily rental buildings, starting at seven units. As residential property, it is assessed at 10% of market value. The state equalizer and local rates apply after that.
Can I appeal if my building’s income does not support the new value?
Yes, and that mismatch is the core of most multifamily appeals. Document actual rents, occupancy, concessions, and expenses, then show the value those numbers support. Appeal windows open township by township every year at the Assessor and the Board of Review.
Do Class 9 or LIHTC properties plan differently?
Yes. Affordable housing programs carry their own filings and compliance calendars. So the incentive paperwork and any appeal need to move together. Pull the current forms from the Assessor and have counsel review both tracks at once.
When should a multifamily owner start preparing?
Before the township window opens, not after the notice surprises you. The evidence file takes time to assemble. Also, the same file serves this cycle’s appeal and the 2027 reassessment response. Portfolio owners can screen with a preliminary review first.
Multifamily Values With the Evidence Attached
PahRoo Appraisal & Consultancy has valued Chicago-area multifamily and commercial property for over two decades. An appraiser holding both MAI and SRA designations leads the firm. Maybe your appeal needs a commercial appraisal with the income analysis attached. Maybe an acquisition or estate calls for broader appraisal services. Either way, the value arrives documented, built from the building’s real numbers and ready for the people who will test it.