What is the maximum late fee in Illinois?

Illinois has no statutory cap on late fees, but fees must be reasonable — courts generally accept up to about $75.00 (5% of the monthly rent) on a rent of $1,500.00. No STATEWIDE cap or required grace period — the fee must be 'reasonable.' Chicago (RLTO: $10/mo on the first $500 of rent + 5% of the excess) and Cook County have binding local caps; check your municipality.

Does Illinois require a grace period for late fees?

No, Illinois does not require a grace period by state law. However, many landlords include a 3-5 day grace period in the lease.

Free Tool

Illinois Late Fee Calculator

Calculate the maximum late fee you can legally charge in Illinois. Check grace periods, fee caps, and compliance with Illinois state law.

State

Monthly Rent

Days Late

Your Proposed Fee

Your Late Fee

$75.00

Compliant

Illinois has no statutory cap; your fee of $75.00 is within the $75.00 courts generally accept (5% of the monthly rent). It must be authorized by the lease.

Rent + Fee

$1,575.00

Grace Period

None required

Court-Accepted Guideline in Illinois (no statutory cap)

$75.00

Illinois Late Fee Law

Grace period: No grace period required by state law

Fee cap: $75.00 — 5% of the monthly rent (guideline, not a statutory cap)

Daily fees: Not typical

No STATEWIDE cap or required grace period — the fee must be 'reasonable.' Chicago (RLTO: $10/mo on the first $500 of rent + 5% of the excess) and Cook County have binding local caps; check your municipality.

Laws change quietly. Colorado rewrote its late-fee rules in 2021, Connecticut in 2023. Get an email when Illinois changes its rules — and what to update in your lease.

Landlord Law Watch — $29/yr →

Next Step

Generate the late fee notice

Turn this calculation into a printable, Illinois-compliant notice you can send to your tenant today — with the statute reference included.

Your Name (Landlord)

Tenant Name

Property Address

Rent Due Date

Fill in the four fields above to generate your notice.

Get your state’s late fee rules + a compliant notice template

Grace periods, fee caps, and what makes a late fee unenforceable. Plus early access to Tenby.

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Illinois Late Fee Rules for Landlords

Illinois does not require a grace period by state law, but most landlords include one in the lease. There is no statutory cap, but the fee must be reasonable — courts generally accept up to about 5% of the monthly rent.

Use the calculator above to check if your proposed late fee complies with Illinois law. Need more tools? Check the Illinois security deposit calculator, or try our prorated rent calculator and rent estimate tool.

For a complete guide to Illinois landlord-tenant law, read our Illinois Landlord-Tenant Law 2026 guide.