Illinois Radon Disclosure, 420 ILCS 46/26 (not 46/25) for Tenant Leases
Illinois landlords renewing or signing a residential lease must give the tenant a written radon disclosure. The requirement lives at 420 ILCS 46/26, not 46/25. Public Act 103-298 (HB 2217), effective January 1, 2024, repealed the old 46/25 and added a new Section 26. Template sites that still cite 46/25 are pointing the reader at a repealed statute.
This post explains what the disclosure covers, why the section number changed, when it applies, what it has to say, and the 90-day test window that lets a tenant terminate the lease if elevated radon is confirmed.
What the disclosure covers
Radon is a radioactive gas that seeps from soil into basements and ground-level spaces. The EPA action level is 4 pCi/L (picocuries per liter). Levels above that increase long-term lung-cancer risk.
Illinois requires landlords of residential units on the ground floor or below to disclose any known elevated radon hazard to tenants. "Known" means the landlord has tested the unit within the last 5 years and the result was above the EPA action level, or was notified by the IEMA (Illinois Emergency Management Agency) of a regional hazard.
Landlords are not required to test. If no test has been done, the disclosure still has to be given, stating that no test has been performed.
Why 420 ILCS 46/25 was repealed
The original Illinois Radon Awareness Act, enacted in 2008, placed the tenant disclosure requirement at 420 ILCS 46/25. That section was a short paragraph with limited penalty language.
Public Act 103-298 (HB 2217), signed in 2023 and effective January 1, 2024, expanded the tenant disclosure. The legislative drafters chose to repeal Section 25 entirely and add a new Section 26 with:
- Clearer language on what the disclosure must contain.
- A 90-day tenant testing window with a right to terminate if elevated.
- Renumbering to align with other ILCS chapters.
Section 25 is now empty. Anyone citing "420 ILCS 46/25" in a 2026 lease is pointing the tenant at a blank section. The Illinois General Assembly's own legislation browser lists Section 26 (042000460K26) as the active section.
When the disclosure is required
420 ILCS 46/26 requires the disclosure at:
- Signing a new residential lease for a dwelling at or below grade.
- Renewal of an existing lease.
- When the landlord obtains new radon test results during an existing tenancy.
The disclosure does NOT apply to:
- Units above the ground floor in buildings of 3+ stories.
- Short-term rentals under 30 days.
- Hotels.
What the disclosure has to say
420 ILCS 46/26 requires the disclosure to include:
- A statement that radon is a known carcinogen.
- Whether the landlord has knowledge of elevated radon in the unit (yes, no, or not tested).
- If tested, the most recent test result and date.
- The IEMA information pamphlet (the one published by the Illinois Emergency Management Agency) attached or referenced.
- The tenant's right to test within 90 days at their own expense.
- The tenant's right to terminate within 60 days of a confirmed elevated result.
The disclosure must be signed by both landlord and tenant and kept with the lease.
The 90-day test and termination right
Under 420 ILCS 46/26(c), a new tenant has a 90-day window from the lease start date to obtain a radon test at the tenant's own expense. If the test result is above 4 pCi/L (the EPA action level) and the landlord does not mitigate within a reasonable time, the tenant has 60 days from the confirmed result to terminate the lease without penalty.
The tenant must:
- Use a licensed radon measurement professional, or
- Use an IEMA-approved home test kit following the kit's protocol.
The termination must be in writing and reference the test result. The landlord cannot retain the security deposit solely because of the termination.
Where to get a compliant disclosure
The disclosure can be written by hand if it contains all the 420 ILCS 46/26 elements. LeaseKit's Illinois residential lease template includes the 420 ILCS 46/26 radon disclosure with the IEMA pamphlet reference, the 90-day test window language, and the 60-day termination right spelled out.
Free blank templates may still cite the repealed 420 ILCS 46/25 or omit the 90-day testing right. Check any template against the current ILGA legislation browser text of Section 26 before using.
This post is informational. Illinois radon disclosure requirements are narrow but strictly enforced in lease disputes. For contested cases, consult an Illinois-licensed attorney.