Radon Levels in Canadian Cities: Which Have the Most Radon?
How many homes have high radon in your city? Figures for 41 Canadian cities and every province from the 2024 Cross-Canada survey of nearly 70,000 homes, in plain language.
October 3, 2026
Radon is an invisible, odourless gas that seeps into homes from the ground. It's the leading cause of lung cancer in people who have never smoked. Health Canada recommends fixing any home where radon is above 200 Bq/m³, called the action level.
In 2024, a research team tested 69,478 homes across Canada. About 1 in 5.6 homes were above the action level, more than double the share found by Health Canada's survey a decade earlier. How common it is depends a lot on where you live.
The short version
- Highest: Regina (1 in 2 homes), Winnipeg (1 in 2.4 homes) and Halifax (1 in 2.6 homes).
- The Prairies stand out. In every Saskatchewan and Manitoba city in the survey, at least 1 in 3.5 homes are above the action level.
- Lowest: Duncan (<1 in 200), Abbotsford - Mission (<1 in 200) and Vancouver (<1 in 200). Low doesn't mean zero: some homes there are still high.
- Basements matter. Measured in the basement, about 1 in 5 Canadian homes are above the action level. Measured on an upper floor, it's about 1 in 12.
Radon levels by city
Homes with radon above the action level, from the 2024 survey. Click a city to open it on the map.
| # | City | Homes above | Level | Homes tested |
|---|---|---|---|---|
| 1 | Regina, SK | 1 in 2 | Very high | 148 |
| 2 | Winnipeg, MBguide | 1 in 2.4 | Very high | 114 |
| 3 | Halifax, NS | 1 in 2.6 | Very high | 2,449 |
| 4 | Trail, BC | 1 in 2.6 | Very high | 93 |
| 5 | Vernon, BC | 1 in 2.6 | Very high | 135 |
| 6 | Prince George, BC | 1 in 3 | Very high | 1,247 |
| 7 | Thunder Bay, ON | 1 in 3 | Very high | 81 |
| 8 | Nelson, BC | 1 in 3 | High | 185 |
| 9 | Kingston, ON | 1 in 3 | High | 39 |
| 10 | Saskatoon, SK | 1 in 3.5 | High | 112 |
| 11 | High River, AB | 1 in 4 | High | 172 |
| 12 | Strathmore, AB | 1 in 4 | High | 71 |
| 13 | Sherbrooke, QC | 1 in 4.3 | High | 143 |
| 14 | Kelowna, BC | 1 in 4.5 | High | 338 |
| 15 | Whitehorse, YT | 1 in 5 | Moderate | 130 |
| 16 | Québec, QC | 1 in 5.6 | Moderate | 1,120 |
| 17 | Saint John, NB | 1 in 5.6 | Moderate | 226 |
| 18 | St. Catharines - Niagara, ON | 1 in 6 | Moderate | 26 |
| 19 | Ottawa - Gatineau, ONguide | 1 in 6 | Moderate | 806 |
| 20 | Edmonton, ABguide | 1 in 6 | Moderate | 3,594 |
| 21 | Guelph, ON | 1 in 6 | Moderate | 102 |
| 22 | Penticton, BC | 1 in 6.3 | Moderate | 56 |
| 23 | Montréal, QC | 1 in 6.3 | Moderate | 2,650 |
| 24 | Calgary, ABguide | 1 in 6.5 | Moderate | 13,645 |
| 25 | Red Deer, AB | 1 in 6.7 | Moderate | 155 |
| 26 | Fredericton, NB | 1 in 7 | Moderate | 439 |
| 27 | Lethbridge, AB | 1 in 7 | Moderate | 271 |
| 28 | Canmore, AB | 1 in 8 | Moderate | 157 |
| 29 | Hamilton, ON | 1 in 8.7 | Moderate | 125 |
| 30 | Chilliwack, BC | 1 in 9.5 | Moderate | 24 |
| 31 | Windsor, ON | 1 in 10 | Lower | 31 |
| 32 | Kitchener - Cambridge - Waterloo, ON | 1 in 12 | Lower | 50 |
| 33 | Grande Prairie, AB | 1 in 14 | Lower | 64 |
| 34 | Moncton, NB | 1 in 14 | Lower | 362 |
| 35 | Kamloops, BC | 1 in 37 | Lower | 90 |
| 36 | London, ON | 1 in 37 | Lower | 76 |
| 37 | Victoria, BC | 1 in 56 | Lower | 160 |
| 38 | Toronto, ONguide | 1 in 59 | Lower | 256 |
| 39 | Vancouver, BC | <1 in 200 | Lower | 337 |
| 40 | Abbotsford - Mission, BC | <1 in 200 | Lower | 19 |
| 41 | Duncan, BC | <1 in 200 | Lower | 16 |
By province and territory
For more on each province, see Radon Levels by Province: A Canadian Guide.
| Province or territory | Homes above | Level |
|---|---|---|
| Manitoba | 1 in 2.3 | Very high |
| Nova Scotia | 1 in 2.7 | Very high |
| Saskatchewan | 1 in 3 | High |
| New Brunswick | 1 in 3.7 | High |
| Yukon | 1 in 4 | High |
| Newfoundland and Labrador | 1 in 4.6 | High |
| Northwest Territories | 1 in 4.6 | High |
| Prince Edward Island | 1 in 5 | High |
| Quebec | 1 in 5.3 | Moderate |
| Alberta | 1 in 5.6 | Moderate |
| Ontario | 1 in 7.6 | Moderate |
| British Columbia | 1 in 16 | Lower |
| Nunavut | 1 in 57 | Lower |
What these numbers can and can't tell you
A city figure tells you how common high radon is around you, not what's in your house. Two houses on the same street can differ many times over, depending on the soil under them, the foundation, and how the house is sealed and ventilated. A home in a “lower” city can still be well above the action level.
The only way to know your level is a test of at least three months, ideally over the winter and in the lowest room you spend time in. It costs far less than most people expect, and if your level is high, a certified professional can usually bring it down for good.
Sources
City and province figures: 2024 Cross-Canada Survey of Radon Exposure in the Residential Buildings of Urban and Rural Communities (Evict Radon National Study, with Health Canada, CAREX Canada and the BC Centre for Disease Control), crosscanadaradon.ca. British Columbia's province-wide figure combines the survey's coastal and interior results. Postal-area estimates on the radon map also use Health Canada's Cross-Canada Survey of Radon Concentrations in Homes (2009–2011) and Statistics Canada census data, under the Open Government Licence – Canada.