Cook County Rent Increase Laws: No Cap, 60-Day Notice Rule

Cook County rent increase laws set no ceiling on how much your landlord can raise the rent, but they do control the notice, the delivery, and the motive behind the increase. In most of suburban Cook County you’re entitled to at least 60 days’ written notice before a higher rent takes effect. Chicago and Evanston run on their own rules, and some properties are exempt from the county ordinance entirely.

Why There’s No Cap on the Amount

The Illinois Rent Control Preemption Act bars every local government in the state, including home-rule municipalities, from enacting any form of rent control.¹² A landlord in Cook County can propose a $50 increase or a $500 increase, and no government body can intervene on the amount alone. The legal fight, when there is one, is about procedure, timing, and motive. An increase that follows the procedural rules is enforceable no matter how steep it feels.

The 60-Day Notice Rule in Suburban Cook County

The Cook County Residential Tenant and Landlord Ordinance (RTLO) governs rental housing across most of suburban Cook County. It requires landlords to give tenants at least 60 days’ written notice before a lease non-renewal or any change in lease terms takes effect.³ A rent increase is a change to lease terms, so this 60-day clock runs whenever a landlord wants to raise the rent at the start of a new lease period or for a month-to-month tenant covered by the ordinance.

The written notice should state the new monthly amount and the date the change begins. Vague language about “adjustments” without a specific dollar figure invites disputes. If a landlord fails to deliver proper written notice within the 60-day window, the increase generally cannot take effect until the full notice period has run from the date you actually received it.

During a fixed-term lease, a landlord typically cannot raise the rent at all unless the lease itself contains a provision allowing mid-term increases. The 60-day rule is about what happens when a lease is ending and the landlord wants to offer renewal at a higher rate.

Who the RTLO Covers, and Who’s Exempt

The RTLO applies in suburban Cook County, but three municipalities run their own tenant-landlord ordinances and sit outside it: Chicago, Evanston, and Mount Prospect. If your unit is in one of those cities, the county’s 60-day notice rule is not your rule.

Even within the RTLO’s reach, several property types are exempt from most of its requirements:

Owner-occupied buildings of six units or fewer where the owner lives on-site.
A single-family home or condo, but only if it is the owner’s sole rental, an owner or immediate family member lived there within the past 12 months, the owner personally manages it, and the owner is not a corporation.
Medical and geriatric facilities, convents, monasteries, religious institutions, educational dormitories, and transitional shelters.
Hotel and motel rooms, bed-and-breakfasts, rooming houses, and boardinghouses, unless a tenant has lived there 32 or more continuous days and pays monthly rent.
Shareholders in a cooperative apartment and buyers under a contract for deed.
Employees whose occupancy is tied to their employment on the premises.

If your rental falls into one of these categories, the RTLO’s notice rules largely don’t apply and the relationship runs on your lease and general Illinois law.³

How the Notice Has to Be Delivered

A correctly worded notice does nothing if delivery can’t be proven. Two methods are reliably defensible:

Personal service, meaning the notice is handed directly to the tenant or to a responsible adult at the residence.
Certified or registered mail, which produces a dated delivery record.

Sliding a note under the door or sending a text message is risky. Electronic delivery may hold up only if the lease specifically authorizes it for official notices and both parties have used that channel before. If delivery is disputed, the landlord has to prove you received the notice, which is why certified mail is the common choice.

Retaliatory Rent Increases Are Barred

The RTLO prohibits landlords from using rent increases to punish tenants for exercising legal rights. Section 42-812 of the Cook County Code covers retaliation, and the protected actions are the predictable ones: reporting code violations, requesting legally required repairs, contacting a government agency about habitability, or joining a tenant organization.⁴

If a landlord raises rent within one year of a tenant taking any of those protected actions, the law presumes the increase is retaliatory, and the landlord has to prove a legitimate, non-punitive reason for the higher price. A tenant who wins a retaliation claim can recover damages and attorney’s fees.⁴

Discriminatory Rent Increases Are Barred

The Cook County Human Rights Ordinance makes it illegal to single out tenants for higher or more frequent rent increases based on protected characteristics, including race, religion, disability, familial status, and source of income. The source-of-income protection means a landlord cannot target tenants who pay with Housing Choice Vouchers for steeper increases or different treatment.

Complaints go to the Cook County Commission on Human Rights, which can impose fines and order compensatory damages. Tenants can also take claims to court. Rent adjustments must track the property and the market, not who the tenant is.

If You Live in Chicago

Chicago sits outside the RTLO and has its own, longer notice requirements through the Fair Notice Ordinance. The required notice is tied to how long you’ve lived in the unit:

More than six months but less than three years: at least 60 days’ written notice before the increase.
Three years or more: at least 120 days.

The longer window for long-term residents reflects the harder search those tenants face for comparable housing.⁵ A Chicago landlord who gives short notice cannot enforce the increase until the required period has run from actual delivery.

If You Live in Evanston

Evanston also falls outside the Cook County RTLO and operates under its own Residential Landlord and Tenant Ordinance. Recent amendments require landlords to provide written notice of lease renewal at least 90 days before the current lease term ends. Evanston’s ordinance has been updated in recent years, so confirm the current notice period with the city’s community development department before relying on any specific figure.

If the Notice Looks Wrong

One point surprises tenants: the Cook County Commission on Human Rights does not enforce the RTLO. The ordinance is enforced through private legal action, so a tenant who believes their landlord violated the notice requirements or retaliated has to file a lawsuit or get legal counsel.³ Discrimination complaints under the Human Rights Ordinance do go through the Commission; procedural RTLO violations don’t.

If a rent increase notice looks too short, retaliatory, or discriminatory, document everything. Save the notice, note the date you received it, and keep records of any complaints or repair requests you made in the months before. That paper trail is what carries weight if the dispute ends up in front of a judge.

Security Deposits When Rent Goes Up

A rent increase often prompts a question about the security deposit. Under the RTLO, deposits are capped at one and a half times the monthly rent.³ If your rent rises and the landlord wants to collect more deposit to match, the new deposit still cannot exceed that ceiling, and any request for the extra money should come with the same written notice and transparency as the rent increase itself.

1
Illinois General Assembly. 50 ILCS 825 – Rent Control Preemption Act
2
Illinois General Assembly. 50 ILCS 825 – Rent Control Preemption Act, Section 10
3
Cook County Government. Residential Tenant Landlord Ordinance
4
Cook County. Residential Tenant Landlord Ordinance Summary
5
City of Chicago. Know Your Rights: Fair Notice Ordinance