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Blog/Radon Mitigation Cost in 2026: State-by-State Breakdown

2026-06-15 · 6 min read

Radon Mitigation Cost in 2026: State-by-State Breakdown

National average is $1,000–$2,500. But cost varies significantly by state, foundation type, and contractor market. Here's what homeowners are actually paying in 2026 across the top 10 high-radon states.

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2026 Radon Mitigation Cost Overview

Radon mitigation costs have increased modestly since 2023, primarily due to labor market tightening in skilled trades. The table below reflects what homeowners in the top 10 high-radon states are actually paying for standard sub-slab depressurization systems in 2026.

Cost by State (Top 10 High-Radon States)

StateAverage Indoor RadonStandard Slab/BasementCrawl SpaceNotes
Iowa8.5 pCi/L$900–$1,600$2,200–$5,000Lowest cost, highest radon; large contractor market
Colorado6.6 pCi/L$1,200–$2,500$2,800–$6,000Higher labor market; EPA Zone 1 statewide
Indiana5.6 pCi/L$950–$1,700$2,300–$5,000State certification required; competitive market
Minnesota5.0 pCi/L$1,100–$1,900$2,500–$5,500State licensure required; strong contractor supply
Pennsylvania4.7 pCi/L$1,100–$2,200$2,500–$6,000Zone 1 across most of state; block foundations add cost
Ohio4.5 pCi/L$900–$1,700$2,200–$4,800Low labor costs; large market; state certification required
Wisconsin4.3 pCi/L$1,000–$1,800$2,300–$5,000Moderate costs; EPA Zone 1 in western/central areas
Montana4.2 pCi/L$1,200–$2,200$2,500–$5,500Smaller contractor market; higher travel costs in rural areas
Illinois4.0 pCi/L$1,000–$2,000$2,400–$5,200IEMA licensure required; competitive Chicago market
Kansas3.9 pCi/L$900–$1,700$2,000–$4,500Below EPA average on radon but Zone 1 in northern areas

Cost by Foundation Type (National Averages)

Foundation type is the primary driver of mitigation cost — more so than geography for most homeowners.

Slab-on-Grade: $800–$2,500

The least expensive to mitigate. One core-drill hole through the slab, one suction pipe, one fan. Most slab homes are mitigated in 4–6 hours. Cost increases with home size (large slabs need multiple suction points) and complex sub-slab conditions.

Poured Concrete Basement: $900–$2,200

Similar to slab systems. The basement floor is the suction point. Some older poured concrete basements have gravel sub-bases that improve sub-slab communication, reducing the number of suction points needed.

Block Foundation Basement: $1,100–$2,500

Block walls have more radon entry points than poured concrete and may require sealing in addition to sub-slab suction. More labor-intensive, but still manageable for experienced contractors.

Crawl Space: $2,500–$8,000+

Crawl spaces are categorically more expensive. A sealed crawl space requires:

  • Full ground cover installation (20-mil polyethylene vapor barrier)
  • Sealing of foundation wall vents
  • Suction fan connected to sub-membrane space
  • Potential wall sealing

The wide range reflects crawl space access, debris removal, existing moisture conditions, and size.

What's Included in a Mitigation Quote

A complete radon mitigation system quote should include:

  • Pre-installation sub-slab communication test
  • Core drilling
  • PVC pipe and fittings (lifetime materials)
  • Fan (5–15 year lifespan; $100–$250 to replace)
  • Exterior weatherproofing
  • Electrical connection (if fan requires outlet or dedicated circuit)
  • Post-mitigation test (often included, sometimes an add-on)
  • Warranty (at minimum a workmanship warranty; many contractors offer satisfaction guarantees)

What's typically NOT included: post-mitigation long-term testing kits, drywall patching if pipe routes through finished walls, or sealing of visible cracks (though many contractors include this).

How to Get Accurate Quotes

  1. Get 3 quotes minimum. Price variation of 20–40% for identical work is normal in competitive markets.
  2. Verify NRPP/NRSB certification for every contractor — not just the company, but the technician doing the work.
  3. Confirm state licensure where required (Indiana, Illinois, Minnesota, Ohio, Pennsylvania, and others).
  4. Ask about post-mitigation testing — the best contractors include a 48-hour short-term test after installation.
  5. Don't accept quotes over the phone. A reputable contractor should inspect the home before quoting.

Find certified mitigators in your state → | Full cost breakdown by foundation type →

Frequently Asked Questions

How much does radon mitigation cost in 2026?

The national average for a standard slab or basement system is $1,000–$2,500 in 2026. Crawl spaces cost significantly more: $2,500–$8,000+. Prices have increased 5–15% from 2023 levels due to labor and material costs, but the competitive contractor market in high-radon states has kept increases modest compared to other home services.

Which states have the lowest radon mitigation costs?

Iowa, Indiana, and Ohio typically have the lowest costs for comparable work — $900–$1,600 for a standard slab — due to lower labor costs and a large pool of certified contractors relative to population. Colorado and Pennsylvania run slightly higher ($1,200–$2,500) due to higher labor markets and more complex geological conditions.

Does a higher quote mean better quality?

Not necessarily. In high-radon markets with many certified contractors, price variation of 20–40% for identical systems is common and reflects market competition, not quality differences. The most important quality signals are NRPP/NRSB certification, state licensure where required, and warranty terms — not price.

Are there any financial assistance programs for radon mitigation?

Some state health departments offer low-income assistance programs. Minnesota, Iowa, and Pennsylvania have had active programs in recent years. Additionally, some home buyer programs allow radon mitigation costs to be rolled into loan amounts at real estate transactions. Check your state radon office for current programs.

Find a Certified Mitigator Near You

Every contractor on RadonBase is NRPP or NRSB certified — mitigators only, no testers.

Browse by State →