Radon in rentals and apartments

Whether renters should test for radon, which apartments are most at risk, how to raise it with a landlord, and where state rules apply.

By the Radon by ZIP editorial team · Last reviewed September 29, 2026 · How we research

Radon does not care whether you own or rent. Renters breathe the same air, and a rental house or ground-floor apartment can have elevated levels.

Which rentals are most at risk

Radon enters from the ground, so the highest levels are usually on the lowest floors. Rented single-family houses, townhouses, basement apartments, and ground-floor units are the most likely to have elevated radon. Upper-floor apartments in tall buildings generally have lower levels, although radon can travel through shafts and shared spaces in some buildings.

Can renters test?

Yes. A short-term test kit is small, inexpensive, and does not require any changes to the unit. Follow the usual placement rules in how to test your home: lowest lived-in level, not in a kitchen or bathroom, at least 20 inches above the floor, with windows closed for short tests. Some state radon programs offer free or discounted kits; see our state pages.

If the result is high

EPA recommends fixing homes at 4 pCi/L or higher and considering a fix between 2 and 4. In a rental, a mitigation system is a building alteration, so it is the owner’s decision and cost unless local law says otherwise.

A practical approach:

Do a follow-up test as EPA recommends, so you have two results. The follow-up planner explains the steps.
Write to your landlord with the results, the dates, and EPA’s guidance. Keep it factual.
Ask whether the building has been tested before and whether the owner will arrange professional testing or mitigation.
Contact your state radon program for information on any state or local requirements. A few states and cities have rules about radon disclosure or testing in rental housing; many do not.

Landlord perspective

For property owners, testing and fixing radon is usually a one-time project that protects tenants and can reduce liability concerns. A working mitigation system and recent low test results are useful records to keep.

Public and assisted housing

Some federal housing programs have radon testing requirements for certain properties. If you live in public or assisted housing, ask the property manager whether the building has been tested.

Bottom line

Test if you live on a low floor or in a house, share results in writing, and use your state radon program for local rules and help.