Radon is a dissolved gas, not a mineral or particle — which means the whole-house filters that handle iron or sediment won't touch it. Here's what removal actually requires.
Standard filtration and softening systems work by trapping particles or exchanging minerals. Radon-222 is a dissolved radioactive gas, and the only effective residential treatments are aeration systems (which off-gas radon before it enters household air) or granular activated carbon (GAC) tanks sized specifically for radon capture.
| Approach | Typical Cost |
|---|---|
| Water radon test kit | $30–$150 |
| GAC tank system | $1,000–$2,500 installed |
| Whole-house aeration system | $2,000–$5,000 installed |
Unlike iron filters or softeners, radon aeration and GAC systems are specialized enough that they're almost always installed by a water treatment contractor rather than purchased as a consumer kit — sizing depends on your specific radon reading and household water usage.
Get a certified water test first. Removal systems are a significant investment — confirm your actual radon-222 level in water through a certified lab before contacting installers, so you know what capacity you actually need.
No. Radon is a dissolved gas, not a particle or mineral, so standard sediment or carbon filters don't remove it. Radon removal requires either aeration systems or granular activated carbon (GAC) tanks specifically designed for gas removal.
Whole-house aeration systems for radon removal typically cost $2,000-$5,000 installed, including professional installation, since these are specialized systems usually installed by water treatment contractors rather than sold as consumer kits.
Only a water test for radon-222 will tell you. EPA guidance suggests considering treatment above 4,000 pCi/L, though some states set different action levels. Test first before considering any removal system.
Use our free decoder to understand what your other well water test results mean alongside radon.
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