Cook County Property Taxes Increased in 2025: What the Numbers Mean for Homeowners
Cook County’s total property-tax burden increased 3.9% for tax year 2025, exceeding both Chicago-area and national inflation. The largest regional increase was concentrated in the north and northwest suburbs, but individual tax bills vary considerably. Homeowners concerned about an increase should check their exemptions, property record, assessed value and applicable appeal deadlines.
The countywide numbers
Cook County property owners will pay approximately $19.9 billion in property taxes for tax year 2025, payable in 2026.
That represents an increase of approximately $743.8 million, or 3.9%, over the previous year.
For comparison, Chicago-area inflation was approximately 3.1% during 2025. Nationally, the annual-average Consumer Price Index increased approximately 2.6%.
Cook County property taxes therefore increased:
- 0.8 percentage point faster than Chicago-area inflation; and
- 1.3 percentage points faster than national annual-average inflation.
Those comparisons describe the growth of the total countywide tax burden. They do not mean that every property owner’s bill increased by 3.9%.
Homeowners absorbed most of the increase
Residential property owners are responsible for approximately $593.4 million, or 80%, of the countywide tax increase.
This continues a multiyear pattern in which homeowners have absorbed most of Cook County’s additional property-tax burden. One contributing factor is that residential property values have generally performed better than many commercial property values, shifting a greater share of the tax burden onto residential property.
That does not mean commercial property taxes universally decreased. Results depend on the property type, location, assessment and applicable taxing districts.
Where did taxes increase the most?
The largest regional increase occurred in the north and northwest suburbs.
Properties in that portion of Cook County underwent their triennial reassessment in 2025. Total property taxes in the region increased approximately $370.8 million, or 6.4%.
Some communities were also affected by increased school, municipal, park, library and other local-government levies, including voter-approved spending.
Chicago experienced a more moderate overall change. The median Chicago property-tax bill increased approximately 2.2%, although Chicago homeowners collectively experienced an increase of approximately 3.2%.
These figures measure different things. A regional total measures all taxes collected in that area. A median measures the change experienced by the homeowner in the middle of the distribution. Neither figure predicts what happened to a particular property.
Why can an individual bill increase?
A property-tax bill can change for several reasons:
- The property’s assessed value increased.
- The property’s assessment increased relative to other property.
- Local taxing districts requested more money.
- Voters approved a referendum.
- The composite tax rate changed.
- The tax burden shifted between residential and commercial property.
- An exemption expired or was omitted.
- A prior assessment reduction no longer applies.
An increased bill does not, by itself, prove that the assessment is incorrect.
What should a homeowner check?
1. Compare the complete annual bills
Compare the total tax for 2025 with the total tax for 2024.
Do not compare only this year’s second installment with last year’s second installment. Cook County’s first installment is an estimated amount equal to 55% of the previous year’s total tax. The second installment completes the calculation using the current assessment, exemptions, equalization factor and tax rate.
2. Verify every applicable exemption
Review the bill to determine whether all eligible exemptions were applied. Depending on the homeowner’s circumstances, these may include:
- Homeowner Exemption
- Senior Citizen Exemption
- Low-Income Senior Citizens Assessment Freeze
- Persons with Disabilities Exemption
- Veterans with Disabilities Exemption
A homeowner who qualified for an exemption that was omitted may be able to apply for a Certificate of Error and obtain a refund for an eligible prior year.
3. Review the property description
Check the Assessor’s records for errors involving:
- Building square footage
- Lot dimensions
- Property classification
- Number of residential units
- Age or condition of the improvements
- Features that the property does not actually have
A factual error can cause an assessment to overstate the property’s value.
4. Evaluate the estimated market value
Compare the Assessor’s estimated market value with recent arm’s-length sales, an appraisal and other credible evidence of the property’s value as of the relevant assessment date.
A homeowner’s disagreement with the tax bill is not itself a basis for an appeal. The relevant question is whether the assessment overstates the property’s value or treats it unfairly compared with similar properties.
5. Examine assessment uniformity
Similar properties should generally be assessed consistently. A homeowner may have a uniformity argument when genuinely comparable properties have lower assessment levels.
The comparison should focus on assessed values and relevant property characteristics—not merely on the neighbors’ final tax bills. Exemptions and different taxing districts can cause similar homes to have different tax bills.
6. Check the applicable appeal calendar
Cook County appeal periods are organized by township. The Cook County Assessor and Cook County Board of Review maintain separate filing schedules.
Missing one filing period does not always mean that every appeal opportunity has been lost, but homeowners should not assume that an appeal can be filed at any time.
What an assessment appeal cannot do
An assessment appeal can potentially reduce an excessive or unequal assessment. It cannot directly reduce:
- A school district’s levy
- A municipality’s spending
- A voter-approved referendum
- The property’s composite tax rate
- The countywide amount that taxing districts have requested
Reducing one property’s assessment changes how the overall tax burden is allocated. It does not reduce the amount local governments seek to collect.
Does an appeal change the bill currently due?
Usually not.
An appeal filed during the current assessment cycle generally affects a future property-tax bill. It ordinarily does not suspend, postpone or eliminate the payment obligation for a bill that has already been issued.
Cook County’s tax year 2025 second installment is due October 1, 2026. Owners should arrange for timely payment even if they are investigating an assessment appeal, missing exemption or other correction.
What if the homeowner cannot pay the entire bill?
Cook County accepts partial payments. Paying part of the balance may reduce the amount on which additional interest accrues, but it does not extend the deadline or eliminate interest on the unpaid portion.
Homeowners with mortgage escrow accounts should also confirm that their servicer received the bill and determine whether the increase will cause an escrow shortage. Spreading an escrow shortage over future mortgage payments can ease the immediate effect, but it does not reduce the underlying tax.
Certain qualifying senior homeowners may also investigate Illinois property-tax deferral options. A deferral is generally a loan secured by the property rather than forgiveness of the tax, so the repayment and interest terms should be reviewed carefully.
The bottom line
Cook County property taxes increased faster than inflation in 2025, with the largest regional increase occurring in the north and northwest suburbs.
Some increases may be mitigated by correcting missing exemptions, fixing inaccurate property information or challenging an excessive or unequal assessment. Other increases result from higher tax rates and local-government levies that an individual assessment appeal cannot eliminate.
The first step is to identify which part of the property-tax calculation changed before deciding whether an appeal or correction is appropriate.
This article is for general informational purposes and is not legal advice.
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