Illinois Late Rent Fee Laws: Limits, Grace Periods, and Penalties

Illinois has no statewide statutory cap on residential late fees — the Landlord and Tenant Act is silent, so a fee must simply be in the lease and survive the common law test that liquidated damages be a reasonable estimate of loss rather than a penalty. Two local ordinances do cap it. Chicago's Residential Landlord and Tenant Ordinance § 5-12-140(h) limits the monthly late fee to $10 on the first $500 of monthly rent plus 5% of the amount above $500, so $1,500 rent yields a $60 maximum. Suburban Cook County's Residential Tenant and Landlord Ordinance § 42-809 is more generous: $10 on the first $1,000 of rent plus 5% of anything above $1,000, so $1,500 rent yields $35. Evanston and Mount Prospect have opted out of the county ordinance and run their own rules.

Neither Illinois statute nor the Chicago and Cook County ordinances require a landlord to wait before assessing a late fee; the fee can attach the day after rent is due if the lease says so. The five-day notice that precedes an eviction for nonpayment is a separate procedural step, not a grace period.

The late fee must be written into the lease to be collectible anywhere in Illinois. Starting January 1, 2027, Public Act 104-0479 additionally requires every non-optional fee — recurring or one-time — to appear on the first page of the lease, and a tenant is not liable for any fee that does not.

Under the Chicago RLTO, an over-cap late fee provision is unenforceable in full, so the landlord collects no late fee at all, and a tenant who is charged under a prohibited lease provision can recover two months' rent in damages plus attorney fees under § 5-12-140 and § 5-12-180. Outside a capped municipality, the exposure is narrower: the clause is simply struck as a penalty.

Under 810 ILCS 5/3-806 the holder of a dishonored check may recover the amount of the check plus the greater of $25 or the reasonable costs and attorney fees of collection, and after proper written notice may pursue treble damages. There is no rental-specific NSF cap in Illinois.

HB 3564 was signed on June 26, 2026 as Public Act 104-0479, adding 765 ILCS 705/35, and companion HB 5234 pushed its effective date to January 1, 2027. It bans move-in fees, caps rental application and background check fees at $50, bars several maintenance and lease-renewal fees, and requires all non-optional fees on page one of the lease — but the enacted text contains no late fee cap and no grace period.

Your address decides your cap, so confirm it before you write the lease: inside Chicago city limits it is $10 plus 5% over $500; in suburban Cook County it is $10 plus 5% over $1,000; in DuPage, Kane, Lake, McHenry, or Will counties there is no cap at all. Both ordinances exempt owner-occupied buildings of six units or fewer, which covers a large share of small Illinois landlords — but if you claim the exemption, you must actually live in the building. Be careful with online guidance: many 2026 articles report a new statewide late fee cap of $10 plus 5% over $1,000 with a five-day grace period, attributing it to HB 3564. That language was in an earlier draft, was removed before passage, and does not appear in the enacted Public Act 104-0479.

• 765 ILCS 705/35 (Pub. Act 104-0479, eff. Jan. 1, 2027)
• Chicago Mun. Code § 5-12-140(h)
• Cook County Code § 42-809 (RTLO)