CO · Boulder County

Radon Test Kits in Longmont, CO

The Longmont seller named by Boulder County is the Extension office at 9595 Nelson Road, phone 303-678-6238. The county does not publish a kit price. Call before you go. The other listed seller is in Boulder, and CDPHE still offers one free Colorado kit per household per year.

Last verified October 1, 2026. Confirm the official page before you travel. Prices and stock change.

Local option

Confirm before you goTesting guidance

Boulder County short-term kit sellers

Boulder County says two local spots sell short-term radon kits: the ReSource Tool Library in Boulder and Boulder County Extension in Longmont.

The county page does not list a price at either seller. It also says kits can be bought at most hardware stores or at sosradon.org.

Call the seller before you go. The county Air Quality Program is a separate contact, 303-441-1564, at 3450 Broadway, Boulder. That office is not listed as a kit counter.

Boulder County Extension

This is the Longmont office.

9595 Nelson Road
Longmont, CO 80501

Phone: 303-678-6238

ReSource Tool Library, Center for ReSource Conservation

6400 Arapahoe Rd.
Boulder, CO 80303

Phone: 303-419-5418

The county says needed radon repairs often cost about the same as other common home repairs, in a range of $800 to $1,200. Air Quality Program hours on the same page are Monday to Friday, 8 a.m. to 4:30 p.m. Those hours are not printed as the sellers' hours. Kit stock was not confirmed, so call first.

Last verified October 1, 2026Radon Testing | Boulder County See something outdated? Report a change.

Available when checkedMail or online kit

Colorado free radon test kit

CDPHE offers a free radon test kit order, one per household per year, and a link to discounted kits.

Who it is for. One free kit per household per year.

Free

Free, one per household per year. CDPHE also links a separate discounted kit order and says store kits often cost about $10 to $50.

Order from the free-kit link on the CDPHE testing page.

Order link published by the agency

CDPHE says radon is found at elevated levels in one out of every two Colorado homes. The department says it does not test your home for you. The discounted kit link on that page goes to https://sosradon.org/test-kits. We did not republish a discounted price because the CDPHE page did not list one.

Last verified October 1, 2026Testing and mitigating your home for radon | CDPHE See something outdated? Report a change.

Prefer a reusable electronic radon monitor?

A short-term test kit is a good low-cost way to screen a home. If you want to see how radon changes over days, weeks, and seasons, or you want a monitor you can reuse in another home, an electronic radon monitor may be a better fit.

Bill's current pick from the Minneapolis guide: Airthings View Radon. It is the simpler radon display. View Plus is the one to compare if you also want a wider indoor air picture.

See current Airthings price Compare radon monitors

If you purchase through our Airthings link, we receive a small percentage of the sale at no additional cost to you. Our affiliate link may provide a discount on eligible products. This helps support the local radon-testing directory.

The product link does not apply a discount by itself. Bill's Minneapolis guide says to add the monitor to your cart, enter your name and shipping, then type ARS10 at checkout. That guide says the code is 10% off eligible Airthings products, it does not apply to items that are already discounted, and it does not stack with other offers. Code: ARS10.

EPA radon zone

EPA classifies Boulder County as Zone 1, its highest radon-potential category. Individual homes can vary, so testing is still the only way to know your home's level. The zone is not a claim that your house is high.

Local radon notes

EPA classifies Boulder County as Zone 1, its highest radon-potential category. Individual homes can vary, so testing is still the only way to know your home's level.

Source: EPA Map of Radon Zones (county file https://www.epa.gov/system/files/other-files/2024-06/radon-zones-202406.json). Checked October 1, 2026.

How to test, and what a result means

Place the kit the way its instructions say, and keep the house closed when the kit requires that. A short test is a screen. It is not the last word if your state wants a follow-up test.

How to test for radon
Understanding radon results
What 4 pCi/L means

Sources

Radon Testing | Boulder County. Verified October 1, 2026.
Testing and mitigating your home for radon | CDPHE. Verified October 1, 2026.
EPA Map of Radon Zones (county file https://www.epa.gov/system/files/other-files/2024-06/radon-zones-202406.json)

How we check programs

A reusable monitor does not have to stay in one house. After you have a reading you trust for your own home, you can lend it to a parent, an adult child, a coworker, a neighbor, or a friend.

Here is an example, not a sale price. If a roughly $100 monitor is eventually used by five households, the equipment cost works out to about $20 per household. Your real price will be whatever the maker charges that day.

Lending a monitor this way does not meet a professional test or a real estate requirement. When you move the device, follow the manufacturer's instructions and start a new measurement.