Radon Test Cost: DIY Kits, Monitors and Professional Tests
Radon testing is one of the cheaper checks a homeowner can run, and it is one of the few that answers a serious health question. The price still varies more than people expect. A basic mail-in kit, a long-term detector, a consumer digital monitor, and a professional continuous-monitor test for a home sale are very different purchases, and the cheapest option is not always the right one for the job. This guide breaks down radon test cost by option, explains what is and is not included in the price, what drives cost up or down, when two tests are needed, and how much retesting after mitigation adds. It also covers free or discounted kits that state programs sometimes offer, which matters along the Colorado Front Range where elevated radon is common. Price ranges here are broad, hedged estimates that shift by vendor, lab and region. The guide summarizes EPA and CDC guidance current as of 2026, names no brands, and is educational only.
Part of our Radon Levels guide — start there for the full picture →
Radon Test Cost at a Glance
EPA’s Citizen’s Guide to Radon describes radon testing as easy and inexpensive, and notes that many kinds of low-cost “do it yourself” test kits are available through the mail and in some hardware stores and other retail outlets. It also says that if you prefer, or if you are buying or selling a home, you can hire a qualified tester. EPA’s Consumer’s Guide to Radon Reduction adds that passive devices, both short- and long-term, are generally inexpensive, while active devices such as continuous radon monitors may cost more.
The table below turns that into rough numbers. Treat every range as a broad estimate; prices vary by retailer, laboratory, region and whether shipping and lab analysis are bundled.
| Test option | Typical cost range (hedged) | Time to result | Best for |
|---|---|---|---|
| Short-term charcoal kit (lab fee included) | Roughly $15 to $40 per kit | 2 to 7 days of testing, plus mailing and lab time | A first screening test in the lowest lived-in level |
| Short-term kit with separate lab fee | Roughly $10 to $25 for the kit, plus a lab fee that may add a similar amount | Same as above | Shoppers comparing kit price against total cost |
| Long-term alpha-track kit | Roughly $25 to $60 per kit | More than 90 days, plus lab time | Estimating the year-round average |
| Pair of short-term kits for a side-by-side test | Roughly $30 to $80 for two | Same as a single short-term test | A quicker decision with more confidence than one kit |
| Consumer digital radon monitor | Roughly $100 to $300 or more, one-time | Readings within a day or two; averages build over weeks | Ongoing awareness between formal tests |
| Professional continuous-monitor test | Roughly $125 to $300 or more per test | At least 48 hours of testing; report often within days | Real estate transactions and documented results |
| Radon add-on during a home inspection | Often lower than a standalone visit; varies widely | Usually the same 48-hour-plus window | Buyers already booking an inspection |
| Free or discounted state program kit | Free to a few dollars, when offered | Same as a standard short-term kit | Homeowners who want a first test at minimal cost |
For a deeper look at how professional fees are set, the radon testing cost guide focuses on hiring a tester, while this page leans toward the full menu of options.
DIY Short-Term Kits: Charcoal and Alpha-Track
Short-term kits are where most homeowners start. EPA’s Citizen’s Guide explains that short-term tests remain in the home for two to 90 days depending on the device, and lists “charcoal canisters,” “alpha track,” “electret ion chamber,” “continuous monitors,” and “charcoal liquid scintillation” detectors as devices most commonly used for short-term testing. The Consumer’s Guide adds that all radon tests should run for a minimum of 48 hours.
Charcoal kits
Charcoal kits are the least expensive option and the most widely sold. They are small sealed tins or packets that sit open for a few days, are resealed, and are mailed to a laboratory. The kit price usually covers the device; whether it also covers lab analysis and return postage depends on the seller. Some kits advertise a low shelf price and then charge a separate lab fee when the kit is registered, so comparing total cost matters more than comparing sticker price.
Timing matters too. Charcoal keeps exchanging radon with the air after the test ends, so the Citizen’s Guide tells users to reseal the package and send it to the lab right away. A kit that sits in a drawer for a week before mailing may not produce a valid result, which turns a cheap test into a wasted one.
Short-term alpha-track and other passive devices
Alpha-track detectors can be used for shorter tests, but they are more often sold for long-term use. Electret ion chambers are more common in professional practice. The what does a radon detector look like guide describes each device, which helps when reading a product listing.
What a short-term kit price usually includes
- The detector and instructions
- A data sheet or online registration for start and end times
- Lab analysis, if bundled
- Return postage, if bundled
- A results report by email or online portal
Items that sometimes cost extra include lab fees, return postage, expedited shipping, and a phone consultation on results. The radon test kit guide walks through buying and returning a kit, and the radon test kits guide compares kit types without brand noise.
Long-Term Kits and Digital Monitors
Long-term kits
EPA’s Citizen’s Guide defines long-term tests as those that remain in the home for more than 90 days, and names alpha-track and electret detectors as commonly used for this type of testing. It explains that a long-term test is more likely than a short-term test to reflect the home’s year-round average, because radon levels vary from day to day and season to season.
Long-term alpha-track kits typically cost somewhat more than a basic charcoal kit, but the price per day of measurement is very low. For a homeowner who is not under a deadline, a long-term test is often the best value for understanding actual exposure.
Consumer digital monitors
Consumer digital monitors are a different kind of purchase: a one-time cost for a device that keeps measuring. They show short-term and running averages and help homeowners see how radon shifts with weather, seasons and HVAC use. For a household that would otherwise buy several kits over the years, a monitor can pay for itself. It is less suited to a single formal decision, because consumer devices are not usually lab-analyzed or certified the way professional instruments are. Many households use both: a lab-analyzed test for the decision, and a monitor for awareness afterward.
Professional Radon Testing for Real Estate
For a home sale, the more common approach is a professional test using a continuous radon monitor. The Citizen’s Guide notes that buyers frequently want tests made by someone who is not involved in the home sale. Professional testers typically bring calibrated equipment with tamper detection, document closed-house conditions, and deliver a written report that both parties can rely on.
Why a professional test costs more
- Equipment. Professional continuous monitors cost far more than kits and need regular calibration.
- Two trips. The tester visits once to place the monitor and again to retrieve it.
- Credentials and insurance. Certified testers carry training and liability costs.
- Reporting. Hourly data, tamper checks and a formal report take time to prepare.
- Speed. Results often arrive within a day or two of retrieval, which matters in a contract window.
Bundling with a home inspection
Many inspectors offer radon testing as an add-on to a general inspection, and bundled pricing is often lower than booking a separate visit because the placement trip overlaps with the inspection. The inspection cost guide covers how add-ons affect the total bill, and the mold and radon testing guide explains when combining the two makes sense and when it does not.
Double Testing, Follow-Up Tests and What They Add
A single short-term result is rarely the end of the story, and the cost of a second test is worth building into the budget from the start.
EPA’s testing steps
The Citizen’s Guide lays out EPA’s recommended steps. Take a short-term test. If the result is 4 pCi/L or higher, take a follow-up test to be sure. For a better understanding of the year-round average, follow up with a long-term test; if results are needed quickly, take a second short-term test. The guide adds that if the first short-term result is more than twice EPA’s 4 pCi/L action level, a second short-term test should be taken immediately.
Two short-term tests in real estate
For home sales, the Citizen’s Guide says the results of two short-term tests done side by side, four inches apart, can be used to decide whether to fix the home, and notes that in a real estate transaction the result of two short-term tests can be used in deciding whether to mitigate. That is why many real estate tests involve either two kits placed together or a continuous monitor, which effectively produces a series of measurements. Budgeting for two kits rather than one is a small cost for a more defensible number. The guide also cautions that when the average of two short-term tests is close to 4 pCi/L, there is less certainty about whether the year-round average is above or below that level.
Retesting after mitigation
If testing leads to a mitigation system, there is another test to plan for. EPA’s Consumer’s Guide to Radon Reduction states that a post-mitigation test should be done within 30 days of system installation, but no sooner than 24 hours after the system is running with the fan on. It recommends an independent follow-up measurement even if the contractor also tests, and says a two- to seven-day measurement is recommended to check the system’s effectiveness. Both EPA guides suggest retesting every two years to make sure radon levels stay low, and the Consumer’s Guide also recommends retesting the lowest lived-in area after a remodel.
Those retests are usually short-term kits, so the ongoing cost is modest. The radon mitigation systems cost guide covers installation pricing, which is a much larger number than any test.
What Drives Radon Test Cost Up or Down
Several factors move the price, and most are within a buyer’s control.
- Bundled versus separate lab fees. The single biggest source of surprise. Check whether the kit price includes analysis and return postage.
- Number of tests. A follow-up test, a side-by-side pair, or testing more than one level adds kits.
- Test length. Long-term kits cost a little more per device but less per day of data.
- Device type. Passive devices are generally inexpensive; active monitors cost more, as EPA’s Consumer’s Guide notes.
- Professional versus DIY. A certified tester’s labor, equipment and reporting account for most of the difference.
- Location and travel. Rural mountain properties may carry trip charges compared with homes in Denver, Colorado Springs or Fort Collins.
- Turnaround time. Rushed results for a contract deadline can cost more.
- Retest policy. Some labs and testers include a retest if a kit fails or a result is invalid; others charge again.
Free or discounted kits from state programs
Many state radon programs have offered free or discounted short-term kits at various times, often during radon awareness campaigns in winter or through local health departments. Availability changes from year to year and by county, so the practical advice is simple: check the state radon program before buying. EPA’s Citizen’s Guide directs readers to their state radon office for information about radon in their area and for lists of qualified testers, and CDC likewise notes that you can contact your state radon office for testing or buy a test kit in a hardware store or online.
Hidden costs to watch for
- A lab fee charged at registration on a kit that looked cheap on the shelf
- A kit that expires before use, or arrives at the lab too late to analyze
- A failed test because the start or end time was not recorded
- Paying for a professional test, then needing another because closed-house conditions were broken
Choosing a Test by Situation and Budget
The right spend depends on the question being asked. A few common situations show how the options line up.
First-time homeowner, no deadline
A single short-term charcoal kit is the usual starting point and the lowest-cost way to get a first number. If the result is below 4 pCi/L, many homeowners stop there and plan to test again in a couple of years or after any major change, such as finishing a basement. If it is 4 pCi/L or higher, EPA’s steps call for a follow-up test. A homeowner with time to spare can make that follow-up a long-term kit, which costs a little more but gives a better picture of the annual average. Total spend for this path is usually the price of one or two kits.
Buyer under contract
Speed and credibility matter more than the lowest price. A professional continuous-monitor test, often booked as an add-on to the general inspection, produces a documented result within the inspection window. Two side-by-side short-term kits are a lower-cost alternative if both parties agree to it and the kits can be placed, retrieved and mailed promptly. The difference in cost is real, but small compared with the price of the home or a mitigation system.
Seller preparing to list
The Citizen’s Guide suggests testing now and saving the results in case a buyer asks, and fixing a problem before selling so it does not complicate the sale. A seller who tests early, with time for a long-term kit or a follow-up, avoids a rushed decision during negotiations. Keeping the lab report with other house records is free and saves questions later.
Household with a mitigation system
The ongoing cost is a short-term kit every couple of years, plus a test after any remodel that affects the lowest lived-in level. A consumer digital monitor is a common add-on here, because it shows at a glance whether levels creep up between formal tests, for example if a fan fails.
Placement mistakes that waste money
The cheapest way to lower radon test cost is to avoid paying for a test that cannot be used. Following the kit instructions and EPA’s placement guidance, which calls for testing in the lowest lived-in level in a regularly used room, away from drafts, kitchens and bathrooms, avoids most failed or misleading results. Recording start and end times, keeping windows and doors closed as instructed, and mailing promptly cover the rest.
Reading Results and Deciding What Comes Next
The cost of a test only pays off if the result is understood. Radon in air is reported in picocuries per liter (pCi/L). CDC notes that EPA recommends fixing a home if radon levels are 4 pCi/L or higher, and that there is no known safe level of radon, so the aim should always be the lowest level. EPA’s Citizen’s Guide adds that radon levels below 4 pCi/L still pose some risk and that, in many cases, they can be reduced.
The radon levels chart guide explains how to read a number in context, and the radon level in basement guide covers why basement readings often run higher. A very high result, such as the scenario discussed in the 25 radon level guide, is a reason to follow up promptly rather than wait for a long-term test.
Why the cheapest test is not always the best value
A low-cost charcoal kit is excellent for a first screen in a home that is not for sale. It is a poor choice when a buyer needs a defensible number within a few days, or when the kit is unlikely to be mailed promptly. A digital monitor is a good long-run investment for curiosity and peace of mind, but it usually does not replace a lab-analyzed or certified test for a decision. Matching the test to the question is how homeowners avoid paying twice.
Why testing matters along the Front Range
CDC describes radon as the second leading cause of lung cancer deaths in the United States after cigarette smoke, with EPA and the Surgeon General’s office estimating more than 21,000 lung cancer deaths each year. CDC also notes radon can build up in any home, whether new or old, sealed or drafty, with or without a basement. Elevated readings are common in many Colorado communities, which makes an inexpensive test one of the better-value checks a Front Range homeowner can make. More background is collected in the radon levels hub and the radon testing pillar.
References
- U.S. EPA. A Citizen’s Guide to Radon (PDF, 2016)
- U.S. EPA. Consumer’s Guide to Radon Reduction: How to Fix Your Home (PDF, 2016)
- CDC. Radon and Your Health
Frequently asked questions
How much does a radon test cost?
As a broad estimate, short-term DIY kits often run about $15 to $40 including lab analysis, long-term kits a bit more, consumer digital monitors roughly $100 to $300, and professional continuous-monitor tests roughly $125 to $300 or more. Prices vary by vendor and region.
Are there free radon test kits?
Sometimes. Many state radon programs have offered free or discounted kits at various times, often in winter. Availability changes, so check the state radon program or local health department before buying.
Does a home sale need two radon tests?
EPA's Citizen's Guide says the results of two short-term tests done side by side can be used to decide whether to fix a home, including in a real estate transaction. Many buyers use either two kits or a professional continuous monitor.
When should radon be retested after mitigation?
EPA's Consumer's Guide says to test within 30 days of installation, but no sooner than 24 hours after the system starts, and recommends an independent follow-up measurement. Retesting every two years is also suggested.
Is a digital radon monitor worth the cost?
It can be for ongoing awareness, since it keeps measuring after one purchase. For a formal decision or a home sale, a lab-analyzed kit or a professional test is usually the expected method.
Weighing a kit against a professional test, or not sure what a result means for a sale? Drop us a line and we will help match the test to the question.
Test your home for radon
Radon is invisible and odorless, so a test is the only way to know your level. A short-term kit gives a first reading in days; a digital monitor tracks it over time.
| Product | Why | Buy |
|---|---|---|
 AirChek Charcoal Radon Test Kit | Lab fee usually included; EPA short-term protocol. | Amazon — $21.95 |
 First Alert RD1 Radon Test Kit | Widely stocked; 48-hour charcoal test. | Amazon — $17.95 |
 Airthings Corentium Home | Digital monitor with a long-term average. | Amazon — $142.99 |