The Cook County RTLO governs suburban Cook County outside Chicago — 30-day return, with a 2×-plus-fees penalty for violations.
Deadline
30 days
under the Cook County ordinance
Penalty
2× + fees
for a violation
Ordinance
RTLO § 42-111
Cook County municipal code
This ordinance governs instead of the state default. For units the RTLO covers, its own 30-day deadline and automatic 2× penalty govern the deposit — lead with the RTLO. The ordinance expressly preserves rights under Illinois state law and other local ordinances (§ 42-115), so state-law claims remain available in parallel; the only state provision it supersedes outright is § 18 of the Mobile Home Landlord and Tenant Rights Act.
The tenant “shall be awarded” twice the security deposit plus reasonable attorney’s fees for a violation of the deposit cap, the installment right, or the 30-day return-and-itemization duty — the three strict-liability duties under § 42-111(M)(1). The separate-account and bank-disclosure duties are enforceable too, but only after the tenant serves written notice and the landlord fails to cure within two business days (§ 42-111(M)(2)).
Attorney's fees may also be recoverable.
Scope: Enacted in 2021, the RTLO covers unincorporated Cook County plus municipalities that lack their own comprehensive ordinance — it does NOT apply in Chicago, Evanston, Oak Park, or other cities with their own rules. It caps deposits at 1.5 months’ rent and requires a separate Illinois account, written bank disclosure, and a signed receipt.
30 days, under the Cook County ordinance. For units the RTLO covers, its own 30-day deadline and automatic 2× penalty govern the deposit — lead with the RTLO. The ordinance expressly preserves rights under Illinois state law and other local ordinances (§ 42-115), so state-law claims remain available in parallel; the only state provision it supersedes outright is § 18 of the Mobile Home Landlord and Tenant Rights Act.
The tenant “shall be awarded” twice the security deposit plus reasonable attorney’s fees for a violation of the deposit cap, the installment right, or the 30-day return-and-itemization duty — the three strict-liability duties under § 42-111(M)(1). The separate-account and bank-disclosure duties are enforceable too, but only after the tenant serves written notice and the landlord fails to cure within two business days (§ 42-111(M)(2)).
Cook County Residential Tenant and Landlord Ordinance § 42-111 (adopted as § 42-811, Ord. 20-3562). We verify these against the ordinance text itself; the date we last checked is shown on this page.
Sources & verification
The Cook County rules on this page were verified against the ordinance text itself:
Last verified against primary sources on .
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Cook County sits on top of Illinois's statewide security deposit law. Read the full Illinois rule →
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