What the Senior Assessment Freeze Actually Does
The Illinois Senior Citizens Assessment Freeze (SCAFP) locks your property's Equalized Assessed Value (EAV) at the year you first qualify. The EAV is the number the tax rate is applied to — not the market value of your home, but one-third of it (or one-tenth in Cook County), adjusted by the state equalization factor.
Once your EAV is frozen, it stays at that level regardless of how much your home's market value rises. If your home appreciates from $280,000 to $380,000 over six years, your assessed value remains at the level it was when you first applied. At a Kane County effective rate of 2.4%, that appreciation would have added roughly $2,400/year in additional tax. The freeze eliminates that increase.
Who Qualifies
- You are 65 years old or older as of January 1st of the application year
- You have a household income of $65,000 or less (all sources: Social Security, pensions, investment income, wages)
- The property is your principal residence
- You have been liable for paying the property taxes (owner, not renter)
The $65,000 income threshold is household income — if you and a spouse both draw income, both are counted. Social Security income that is not subject to federal income tax is still counted for SCAFP purposes. This catches some applicants off guard: even if your Social Security is not taxable federally, it counts toward the $65,000 threshold.
How Much It Saves — By County and Home Value
| Scenario | Without Freeze | With Freeze (Value Locked at Purchase) | Annual Savings |
|---|---|---|---|
| $280K home, 10% appreciation, DuPage (2.0%) | $6,160/yr | $5,600/yr | ~$560/yr |
| $320K home, 15% appreciation, Kane (2.4%) | $8,832/yr | $7,680/yr | ~$1,152/yr |
| $350K home, 20% appreciation, Lake (2.5%) | $10,500/yr | $8,750/yr | ~$1,750/yr |
| Cumulative savings over 10 years (Lake, $350K) | — | — | ~$8,750–17,500 |
In high-appreciation markets and high-rate counties — Lake County especially — the SCAFP can save $1,000–$2,000/year and $10,000–$20,000 over a decade. In lower-rate counties like DuPage with slower appreciation, savings are meaningful but smaller.
The Annual Re-Application Requirement — The Most Common Way to Lose It
This is the critical fact most seniors miss: the SCAFP is not automatic. You must re-apply every single year to maintain the freeze. Miss the deadline and your assessment reverts to current market value for that tax year — there is no grace period, no automatic renewal, and in most counties no notification that your application was not received.
Cook County
Deadline: typically March 1st. Apply at the Cook County Assessor's office or online at cookcountyassessor.com. The Cook exemption is higher — $10,000 EAV reduction — than collar counties.
DuPage County
Deadline: typically July 1st. Apply at the DuPage County Supervisor of Assessments. Forms available at dupageco.org or by mail. Phone: (630) 407-5858.
Kane County
Deadline: typically July 1st (by township deadline which varies). Apply through your local township assessor or the Kane County Assessment Office. Check kanecountyassessor.com.
Will County
Deadline: typically July 1st. Apply at the Will County Supervisor of Assessments. willcountyillinois.com has current forms and deadlines. Some townships have different schedules.
Lake County
Deadline: typically July 1st. Apply at the Lake County Assessment Office. lakecountyil.gov. High-rate county makes the freeze most valuable here.
McHenry County
Deadline: typically July 1st. Apply at the McHenry County Assessment Office or through your township. co.mchenry.il.us for current forms.
How to Apply — Step by Step
Obtain the PTAX-340 Form
The standard Illinois SCAFP application form is PTAX-340. Download from your county assessor's website, pick up at the county office, or call and request one by mail. Some counties have their own supplemental forms.
Gather Documentation
You will need proof of age (driver's license or passport), proof of principal residence (Illinois driver's license with current address or utility bills), and income documentation. Income documentation typically means copies of your federal Form 1040 or SSA-1099 and any pension 1099-R forms.
Calculate Household Income
Include all household income: Social Security (gross amount — the full benefit, not just the taxable portion), pension distributions, IRA/401(k) withdrawals, wages, investment income, rental income. If your total is near $65,000, count carefully.
Submit Before the Deadline
Submit in person, by mail, or online depending on your county. Get confirmation of receipt. Note the date. Put next year's deadline in your calendar immediately.
Verify It Applied on Your Next Tax Bill
When your next property tax bill arrives, verify the exemption is reflected. The EAV on your bill should match the frozen year. If it increased to market value, your application may not have been processed — contact the assessor's office immediately.
The Four Illinois Senior Exemptions — Know All of Them
The SCAFP is the most valuable but it is not the only senior property tax tool:
| Exemption | What It Does | Income Limit | Annual Application? |
|---|---|---|---|
| Senior Citizens Assessment Freeze (SCAFP) | Freezes EAV at base year | Under $65,000 | YES — every year |
| Senior Homestead Exemption | $5,000 EAV reduction (Cook: $8,000) | None | No — one-time |
| Senior Citizens Real Estate Tax Deferral | State pays your tax as a 5% loan | Under $65,000 | YES — every year |
| Circuit Breaker / Property Tax Relief Grant | Up to $700 rebate | Income-based | YES — annually |
The Senior Homestead Exemption is automatic once established — no annual renewal. The SCAFP requires annual renewal. Stack both: the homestead exemption reduces your EAV permanently and the freeze prevents it from rising. Combined, they represent the maximum property tax reduction available to eligible Illinois seniors.
Questions About Illinois Property Tax Planning?
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Talk to an AgentRelated: Illinois Retirement Income Tax Exemption · Cook County Property Tax Guide · DuPage County Property Tax Guide · Chicago Metro 55+ Communities