Illinois Security Deposit Rules 2026: A Landlord's Guide

TL;DR: Illinois has no statewide cap on how much a landlord can charge for a security deposit, but landlords with 5 or more units in a building must give tenants an itemized deduction statement within 30 days of move-out and refund the balance within 45 days. Landlords with 25 or more units must pay annual interest on deposits held over six months, and Chicago's Residential Landlord Tenant Ordinance adds even stricter timelines and penalties.

_Last reviewed: August 2026 · 6 min read_

Getting a security deposit wrong in Illinois can cost you more than the deposit itself. Between the statewide Security Deposit Return Act, the separate interest law, and Chicago's own ordinance, the rules depend heavily on where your property sits and how many units you own. Here's what actually applies to you in 2026.

Okoniq Property Hub keeps move-in and move-out photos, deduction receipts, and refund dates in one place, so you have proof ready if a deposit dispute ever lands in small claims court.

How much can an Illinois landlord charge for a security deposit?

Illinois sets no statewide dollar limit on security deposits. You can charge one month's rent, two months', or more, unless a local ordinance says otherwise. Some municipalities, including parts of Cook County under its Residential Tenant Landlord Ordinance, impose their own caps or notice requirements, so check your specific city or county code before setting the amount in your lease.

What Illinois does regulate closely is what happens after the tenant moves out, not what you charge going in. That distinction trips up a lot of owner-operators who assume the whole topic is governed by one statewide rule. Spell out the deposit amount and any move-in fees clearly in the lease itself; a vague clause is one of the most common issues covered in 7 lease clauses every independent landlord should understand.

How long does a landlord have to return a security deposit in Illinois?

Landlords with 5 or more units in a building or complex must send an itemized statement of any deductions within 30 days of the tenant vacating, and must include copies of paid receipts for any single repair over $50. If deductions are listed but receipts aren't provided within that window, or if there are no deductions at all, the full deposit is due back within 45 days of move-out.

Miss either deadline and you lose your right to withhold anything, even for legitimate damage. Courts have consistently sided with tenants when landlords skip the paperwork step, regardless of how much actual damage existed. Keep dated photos from move-in and move-out and a written itemization template ready before the lease even ends, so the 30-day clock doesn't catch you off guard.

Does Illinois require landlords to pay interest on security deposits?

Yes, if you own 25 or more units statewide (or 5 or more in a single building), the Illinois Security Deposit Interest Act requires you to pay interest annually on any deposit held longer than six months. The applicable rate changes periodically, so verify the current figure before calculating what's owed rather than reusing last year's number.

This requirement catches landlords by surprise when they scale up from a few doors to a portfolio that crosses the 25-unit threshold. If you're unsure whether interest applies to your situation, our breakdown of security deposit interest obligations walks through the thresholds and how to calculate what's due.

| | Under 25 units statewide | 25+ units statewide | |---|---|---| | Interest on deposit | Not required by state law | Required annually if held 6+ months | | Itemized deduction statement | Required if 5+ units in building | Required | | Refund deadline | 45 days | 45 days |

What are Chicago's extra security deposit rules?

Chicago's Residential Landlord Tenant Ordinance (RLTO) layers stricter requirements on top of the state law for any property inside city limits. Deposits must be held in an Illinois bank, and the landlord must give the tenant a receipt naming the bank and account. Landlords must send written notice of any deductions within 30 days, and if a tenant requests copies of receipts, they must be provided within 7 days.

Interest is required annually under the RLTO if the tenancy runs 6 months or longer, at a rate the city comptroller sets each year, so confirm the current-year rate rather than assuming it matches a prior year. The bigger risk in Chicago is the penalty structure: a landlord who willfully violates these deposit rules can be liable for twice the deposit amount plus $200, on top of the tenant's attorney fees. That's a meaningfully higher stakes environment than the rest of the state, and it's worth reviewing the full ordinance text or talking to a local attorney if any of your units fall inside city boundaries.

What's the best way to stay on top of these deadlines?

Most disputes come down to missed dates and missing paperwork rather than genuine disagreement over damage. A simple system, whether it's a spreadsheet or dedicated software, that flags the 30-day and 45-day deadlines the moment a tenant gives notice removes most of the risk. Several owner-operators running multiple units use tools compared in our rundown of property management software for independent landlords specifically to automate these reminders alongside rent tracking.

FAQ

Can Illinois landlords charge a non-refundable move-in fee instead of a deposit?

Illinois doesn't prohibit non-refundable fees outright, but calling something a "fee" instead of a "deposit" doesn't exempt it from these laws if it functions the same way. Courts look at substance over labels, so a fee held to cover potential damage is generally treated as a deposit.

Can a landlord deduct for normal wear and tear in Illinois?

No. Illinois law, like most states, only allows deductions for damage beyond normal wear and tear, such as holes in walls, stains, or broken fixtures, not for faded paint or worn carpet from ordinary use over a multi-year tenancy.

Do these deposit rules apply to month-to-month tenants?

Yes. The 30-day itemization and 45-day refund rules under the statewide Security Deposit Return Act apply regardless of whether the tenancy was a fixed-term lease or month-to-month, as long as the building meets the 5-unit threshold.

What should be included in a security deposit itemization letter?

A compliant itemization should list each deduction with a specific dollar amount, a brief description of the damage or unpaid charge, and attached copies of receipts for any repair over $50, sent to the tenant's last known address within 30 days of move-out.

Does a small landlord with only 2 or 3 units have to follow the same deposit rules?

The 30-day itemization requirement under the state Security Deposit Return Act only applies to buildings with 5 or more units, so an owner-operator with 2 or 3 units isn't bound by that specific statute, though local city ordinances may still apply and general contract law still requires returning deposits in good faith.

This is educational information, not legal advice. Consult a landlord-tenant attorney licensed in Illinois, and check your specific city or county ordinance before setting deposit policies.