Radon when you buy, sell, or rent
14 states require a radon disclosure or notice when a home sells. 4 protect renters.
Selling
- Colorado: Sellers must disclose known radon test results and any radon concentrations to buyers. Source
- Delaware: Sellers must notify buyers of radon risk and share any known radon test results. Source
- Florida: Every sale contract must carry the state's standard radon gas warning statement. Source
- Illinois: Sellers must give buyers the state radon pamphlet and disclose any known elevated test results before the sale. Source
- Iowa: Iowa sellers must disclose any known radon test results and give buyers the state radon fact sheet. Source
- Kansas: Every Kansas home sale contract must include a state-required radon notice warning buyers about possible exposure. Source
- Massachusetts: Buyers get a state home inspection brochure that covers radon, lead paint, and termites. Source
- Minnesota: Sellers must disclose known radon test results in writing and give buyers an MDH booklet. Source
- Montana: Sellers must give buyers a radon disclosure statement before or when signing a purchase contract. Source
- New Hampshire: Sellers must give buyers a signed radon notification before signing a real estate purchase contract. Source
- New Jersey: Sellers must give buyers radon test results and proof of mitigation when signing a sale contract. Source
- North Dakota: Sellers must disclose in writing any known radon test results before signing a sale agreement. Source
- Rhode Island: Sellers must state on the disclosure form that radon exists in Rhode Island and testing is advisable. Source
- Virginia: Sellers use the state disclosure form, which tells buyers to check radon zone maps themselves. Source
26 more states use a general seller disclosure form that may ask about radon.
Renting
- Colorado: Before a lease is signed, Colorado landlords must give tenants a signed written radon warning, any known radon test results and mitigation details, and the state radon brochure, and a tenant on a lease longer than one year may void it if the landlord skips the disclosure or does not try to mitigate within 180 days of a 4.0 pCi/L professional result. C.R.S. 38-12-803 (added by SB23-206); tied to the warranty of habitability at C.R.S. 38-12-503(2.4)
- Florida: The same statutory radon warning notice required for home sale contracts also applies to residential rental agreements in Florida, except for short-term stays of 45 days or less. Section 404.056(5), Florida Statutes
- Illinois: Landlords must give tenants the state 'Radon Guide for Tenants' pamphlet, any records showing a radon hazard, and a signed radon disclosure form, and tenants who test high in the first 90 days may end the lease if the landlord does not mitigate. 420 ILCS 46/26 (Illinois Radon Awareness Act, Sec. 26)
- Maine: Maine landlords must have rentals tested for radon by a registered tester and give tenants the results in writing, and either side may end the lease if a test reads 4.0 pCi/L or higher. 14 M.R.S. 6030-D
House on a private well? Well water testing rules when a home sells.
From each state's own law or radon program page, checked October 1, 2026. This is not legal advice.