Radon Mitigation Cost in Massachusetts (2026)

Radon in Massachusetts

Massachusetts is a high-radon state from Berkshire County to the South Shore. The bedrock underlying most of the state — granite, gneiss, and schist belonging to the New England Batholith — contains significant uranium and releases radon throughout the soil column above it.

The highest-risk areas include:

• Western Massachusetts (Berkshire, Hampshire, Hampden, and Franklin counties): granite and metamorphic terrain, Zone 1 throughout
• MetroWest and central MA (Worcester, Middlesex counties): granite-rich Dedham and Milford formations, frequently elevated
• North Shore (Essex County): similar Avalon Zone bedrock, Zone 1–2
• Boston metro and South Shore: Zone 2, but individual homes — particularly in older suburbs with full basements — test above the action level regularly
• Cape Cod and Islands: Zone 2–3, coastal sediment geology, generally lower but not zero risk

Cost by Foundation Type

Finished Basement: $1,100–$2,500

Massachusetts's cold climate makes full basements nearly universal. This is the predominant mitigation scenario in the state.

• Unfinished basement: $1,100–$1,700
• Partially finished: $1,500–$2,200
• Fully finished, complex routing: $1,900–$2,500

Crawl Space: $2,800–$6,000+

Older New England homes — Victorian-era triple-deckers, Cape Cods, and colonial farmhouses — often have crawl spaces with stone foundation perimeters and rocky sub-floors.

• Standard crawl space: $2,800–$4,200
• Stone foundation, limited access: $4,000–$6,000+

Slab-on-Grade: $1,000–$2,000

Less common in Massachusetts's older housing stock, but found in some 1960s–1990s ranch construction and newer development.

Massachusetts-Specific Cost Factors

Boston labor market: Greater Boston contractor rates are among the highest in New England — expect to pay 20–35% above national averages. Western Massachusetts and the Springfield area run lower.

Old housing stock: Massachusetts has some of the oldest housing in the country. Pre-1900 homes with stone foundations, hand-dug basements, and brick perimeter walls require specialized assessment before standard depressurization can be applied. Experienced Massachusetts contractors handle these configurations, but expect to pay more.

Well water radon: Massachusetts has significant private well usage, particularly in rural areas of Worcester, Hampshire, and Berkshire counties. If you're on a well and have elevated air readings, ask about water testing. Radon in water is a separate treatment system.

No state licensing: Massachusetts does not license radon contractors at the state level. Quality varies significantly. Always verify NRPP or NRSB certification at radonproficiency.org before signing a contract.

Real estate: Massachusetts's active real estate market means radon testing is routine in home purchase transactions, particularly west of Route 128. Having a current test result and a working system is increasingly a selling expectation, not just a disclosure requirement.

Getting Quotes

Get at least two quotes. The Boston metro has enough certified contractors to create real price competition. Western Massachusetts and the Pioneer Valley have fewer options — budget more time for scheduling and potentially more for contractor travel.

Massachusetts Resources

• MA Dept of Public Health Radon Program: mass.gov/radon
• Verify NRPP: radonproficiency.org
• Verify NRSB: nrsb.org

Find certified radon mitigators in Massachusetts →