Updated for 2026

Illinois Security Deposit Laws & Calculator

Illinois has a split return deadline — 30 days with deductions or 45 days without. Chicago renters have even stronger protections under the city's own Residential Landlord and Tenant Ordinance (RLTO), which operates independently from state law and requires annual interest payments to tenants.

Calculate My Refund Generate Demand Letter

Illinois Security Deposit — Quick Facts

Return Deadline
30 / 45 Days
30 days (with deductions) / 45 days (no deductions)
Maximum Deposit
No State Limit
Chicago: 1.5 months (unfurnished)
Penalty for Bad Faith
2× + Court Costs
Plus attorney fees
Interest Required
✓ Yes (25+ units)
Chicago: all buildings
Applicable Law
765 ILCS 710/1
Chicago Renters: The RLTO Gives You Stronger Rights

If you rent within the City of Chicago, your security deposit is governed by the Chicago Residential Landlord and Tenant Ordinance (RLTO) — not just state law. The RLTO is significantly more protective than Illinois state law in several ways:

  • Interest required on ALL buildings — not just 25+ units. The interest rate is set annually by the City Comptroller.
  • Deposit cap of 1.5 months' rent for most unfurnished units.
  • 30-day return deadline for all situations (no split deadline like state law).
  • Itemized receipts required — your landlord must attach actual receipts or invoices for any repair deductions.
  • Annual interest statements — landlords must provide written accounting of interest earned each year.

The RLTO applies to most residential rentals in Chicago — check Chicago's official renter resources to confirm whether your unit is covered.

Calculate Your Illinois Deposit Refund

Enter your deposit and move-out date to see your landlord's exact deadline, any interest owed, and penalties for late return.

Open Full Calculator Generate Demand Letter

Illinois Security Deposit Law — Explained

Illinois's Split Deadline: 30 Days vs. 45 Days

Under 765 ILCS 710/1, Illinois landlords face two possible deadlines depending on whether they plan to make deductions:

If your landlord intends to make deductions from your deposit, they must return the remaining balance — along with an itemized written statement of deductions and supporting documentation (receipts or invoices for any repair work) — within 30 days of you vacating the unit.

If they plan to return the entire deposit with no deductions, they have up to 45 days. In practice, most landlords who haven't sent anything by day 30 have either missed their deadline for deductions or are about to face a claim.

The Itemized Statement Requirement

Illinois law is specific about what a proper deduction notice must include. It's not enough to write "damage repairs: $400." Your landlord must attach actual receipts, paid bills, or contractor invoices for each claimed deduction. Courts routinely reject vague or unsubstantiated deduction lists. If your landlord's itemized statement lacks documentation, those deductions can be successfully challenged in small claims court.

What Your Landlord Can Deduct

Illinois landlords may deduct for unpaid rent, utility charges owed under the lease, and physical damage to the unit beyond normal wear and tear. Normal wear and tear — minor scuffs and marks from furniture, small nail holes from pictures, carpet worn from regular foot traffic, and paint fading over time — cannot legally be deducted. If your landlord charges to repaint an apartment that was already several years old at move-in, that's likely not a valid deduction.

Interest Requirements: 25+ Units Statewide, All Buildings in Chicago

Illinois state law requires landlords to pay interest on security deposits only for buildings with 25 or more units. Interest must be paid annually and calculated at the rate set by the Illinois Comptroller. If your landlord owns a large building and has never paid you interest, they may already owe you money.

Chicago's RLTO removes the building-size threshold entirely. All Chicago landlords covered by the RLTO must pay annual interest on deposits, at the rate published each year by the City Comptroller. If your Chicago landlord has never paid interest, they owe you every year's worth of interest since you moved in — this can add up significantly on multi-year tenancies.

Bad Faith Penalty: 2× the Withheld Amount

A landlord who wrongfully retains a deposit in bad faith — intentionally and without legitimate justification — can be ordered by a court to pay 2× the amount wrongfully withheld, plus court costs and attorney fees. Bad faith is a legal determination, so the more documentation you have showing the landlord's lack of justification (no itemized statement, no receipts, ignored demand letters), the stronger your case.

Chicago Deposit Cap: 1.5 Months' Rent

Unlike state law, which sets no deposit cap, the Chicago RLTO limits security deposits on most unfurnished units to 1.5 months' rent. If a Chicago landlord charged you more than that, they violated the ordinance and owe you a refund of the excess — potentially with interest and penalties on top.

What to Do If Your Landlord Is Late

  1. 1
    Document your move-out thoroughly Take dated photos and video of every room, closet, and appliance. Compare them to your move-in photos. Return keys in person or via mail with delivery confirmation, and note the exact date.
  2. 2
    Provide your forwarding address in writing Email your landlord your new address on or before move-out day. This creates a clear record and removes any excuse for delayed return.
  3. 3
    Check if you're owed unpaid interest If your building has 25+ units statewide, or if you're in Chicago, calculate whether your landlord has been paying annual interest. If not, add that to your demand.
  4. 4
    Send a formal demand letter on day 31+ Use RenterCalc's demand letter generator to create a letter citing 765 ILCS 710/1 (or Chicago RLTO if applicable), listing the deposit amount, any unpaid interest, and demanding return within 14 days.
  5. 5
    File in Illinois Small Claims Court Illinois small claims handles cases up to $10,000. You can sue for the deposit, unpaid interest, and the 2× bad faith penalty if applicable. The process is straightforward for self-represented plaintiffs.
  6. 6
    Chicago renters: contact a tenant rights organization Organizations like the Metropolitan Tenants Organization or Lawyers' Committee for Better Housing offer free guidance on RLTO rights and may assist with your case.

Illinois Security Deposit FAQ

How long does a landlord have to return a security deposit in Illinois?
Illinois has a split deadline under 765 ILCS 710/1. If making deductions, your landlord must return the remaining balance with an itemized statement within 30 days. If returning the full deposit with no deductions, they have 45 days. Chicago landlords under the RLTO must return deposits within 30 days in all cases.
What can an Illinois landlord deduct from my security deposit?
Allowable deductions include unpaid rent and damage beyond normal wear and tear. Your landlord must provide a written itemized list with attached receipts or invoices within 30 days of move-out. Undocumented or vague deductions are legally vulnerable. Normal wear — minor scuffs, small nail holes, regular carpet wear — cannot be deducted.
What is the penalty for not returning a security deposit in Illinois?
Under 765 ILCS 710/1, a bad-faith landlord can be ordered to pay 2× the amount wrongfully withheld plus court costs and attorney fees. Chicago's RLTO has similar penalty provisions, and landlords who fail to pay required annual interest face additional liability for the unpaid interest plus damages.
Does Illinois require interest on security deposits?
Yes — for buildings with 25 or more units statewide. Interest must be paid annually at the rate set by the Illinois Comptroller. Chicago's RLTO requires interest on all covered rentals regardless of building size, at a rate published annually by the City Comptroller. If your landlord has never paid interest on your deposit, they may owe you back-interest for every year of your tenancy.
How do I get my security deposit back in Illinois?
Provide your forwarding address in writing, document move-out with photos, and give proper lease notice. After day 30 without a proper return or itemized statement, send a demand letter citing 765 ILCS 710/1 (or Chicago RLTO if you're in Chicago). Include any unpaid interest in your demand. File in Illinois small claims court (limit: $10,000) if your landlord doesn't respond within 14 days.

Ready to Calculate Your Illinois Refund?

It takes less than 60 seconds. Free for every renter — including Chicago RLTO calculations.

Use the Calculator → Generate a Demand Letter →