Radon Levels by Province: A Canadian Guide

Not all of Canada is the same

Radon comes from uranium and radium in the ground. Some parts of Canada sit on geology that produces significantly more radon than others. The result is that where you live has a major influence on your radon risk — not the only factor, but a significant one.

Health Canada's cross-Canada survey, conducted from 2009 to 2011, tested radon in over 14,000 homes across every province and territory. It remains the largest national dataset on indoor radon in Canada. More recent regional studies have confirmed and refined its findings.

Here's what the data shows.

Saskatchewan — Highest risk in Canada

Saskatchewan has the highest average indoor radon concentrations of any province. The geological makeup of the province — particularly the Canadian Shield and ancient sedimentary rock — releases radon at higher rates than most of the country.

Health Canada's survey found that approximately 26% of homes in Saskatchewan had radon levels above 200 Bq/m³ — more than twice the national average. In some cities and rural areas, the proportion is even higher.

If you live in Saskatchewan and haven't tested, testing is strongly recommended. This isn't a case where average numbers are reassuring — the distribution is wide, and your specific home may be much higher or lower than the provincial average.

Average indoor level: ~200+ Bq/m³

Manitoba — Second highest in Canada

Manitoba's radon situation is similar to Saskatchewan's. The provincial geology, particularly in southern Manitoba and the Winnipeg area, produces elevated radon. Health Canada's survey found that roughly 17% of Manitoba homes exceeded 200 Bq/m³.

Winnipeg has been the subject of specific radon awareness campaigns. The city's residential areas vary considerably, with some neighbourhoods having consistently higher readings than others.

Average indoor level: ~160 Bq/m³

New Brunswick — Elevated in many areas

New Brunswick has higher radon concentrations than many Canadians would expect, driven by granitic geology in parts of the province. The Health Canada survey found approximately 8% of homes above 200 Bq/m³, but some areas are significantly higher than the provincial average.

Homeowners in the central and northern parts of the province should consider testing a priority.

Average indoor level: ~100–120 Bq/m³

Alberta — Moderate to elevated, highly variable

Alberta has significant regional variation. Southern Alberta, including Calgary and surrounding areas, tends to have higher radon levels. Northern Alberta is generally lower. The province-wide average sits in the moderate range, but that average masks areas with quite high concentrations.

Calgary has been identified as one of the Canadian cities with notable radon risk, and several local awareness initiatives have reflected this.

Average indoor level: ~80–100 Bq/m³

Ontario — Broadly moderate, with regional pockets

Ontario's average is close to the national mean, but the province is large and varied. Northern Ontario, particularly areas overlying the Canadian Shield, tends to have higher radon. Southern Ontario, with its clay-rich soils, is generally lower.

The Health Canada survey found approximately 4% of Ontario homes above 200 Bq/m³. This is below the national average, but given Ontario's population, it still represents a substantial number of homes.

Average indoor level: ~60–80 Bq/m³

British Columbia — Variable by region

BC's radon profile is complicated by its geography. Interior BC, particularly the Kootenay and Thompson-Okanagan regions, has higher radon concentrations due to granitic bedrock. Coastal areas, including Metro Vancouver, tend to be lower.

If you live in the BC Interior, your radon risk is meaningfully higher than the provincial average suggests.

Average indoor level: ~50–80 Bq/m³

Quebec — Generally lower, but test if in high-risk geology

Quebec's average indoor radon levels are among the lower in the country. However, areas underlain by Canadian Shield rock — much of northern Quebec — have higher concentrations. Urban Quebec (Montreal, Quebec City) sits on different geology and tends to run lower.

Average indoor level: ~40–60 Bq/m³

Atlantic Canada (Nova Scotia, PEI, Newfoundland)

Nova Scotia has moderate radon levels with some regional variation tied to local geology. Prince Edward Island is generally low. Newfoundland and Labrador has limited data but some areas with elevated concentrations.

The North (Yukon, NWT, Nunavut)

Data from northern Canada is less comprehensive, but what exists suggests that Yukon and parts of the NWT have elevated radon due to local geology. If you live in northern Canada, testing is recommended.

What this means for you

Provincial averages give you context, but they don't determine your home's radon level. Two homes on the same street can have very different readings based on foundation type, ventilation, construction, and local soil conditions.

The only way to know your home's level is to test it. A long-term test kit costs $30–$60 and takes 90 days. Given what we know about radon's health impacts — it's the second leading cause of lung cancer in Canada — the investment is worth it regardless of where you live.

If you're in Saskatchewan, Manitoba, New Brunswick, or parts of Alberta and BC, the case for testing is especially strong.

Resources

• Check your province's radon risk rating — our quick province lookup tool
• How to interpret your test result
• Find a certified radon contractor in your province