SmogRank / World / North America / Canada

Most polluted cities in Canada

60 measured cities, last 24 hours; 1 above the WHO 24-hour guideline. Worst: Nepean at 15.1 µg/m³, #119 in the world.

Quebec: 17 measured citiesSaskatchewan: 3 measured citiesYukon: 1 measured cityNorthwest Territories: 1 measured cityBritish Columbia: 27 measured citiesAlberta: 10 measured citiesManitoba: 1 measured cityOntario: 28 measured citiesNew Brunswick: 5 measured citiesNewfoundland and LabradorNova Scotia: 2 measured citiesPrince Edward Island: 1 measured city#60 Yellowknife: 0.0 µg/m³#59 Winnipeg: 0.1 µg/m³#58 Prince Albert: 1.8 µg/m³#56 Milton: 2.1 µg/m³#57 St. Albert: 2.1 µg/m³#55 Sydney: 2.3 µg/m³#54 Fort McMurray: 2.5 µg/m³#53 Charlottetown: 2.9 µg/m³#52 West Vancouver: 3.4 µg/m³#51 Dartmouth: 3.7 µg/m³#50 Airdrie: 4.0 µg/m³#49 Coquitlam: 4.2 µg/m³#48 Saint John: 4.3 µg/m³#46 Medicine Hat: 4.4 µg/m³#47 Swift Current: 4.4 µg/m³#44 Calgary: 4.6 µg/m³#45 Fredericton: 4.6 µg/m³#40 Chilliwack: 4.7 µg/m³#41 Moncton: 4.7 µg/m³#42 Port Coquitlam: 4.7 µg/m³#43 Rouyn-Noranda: 4.7 µg/m³#39 Sherbrooke: 4.8 µg/m³#38 Saskatoon: 5.0 µg/m³#37 Drummondville: 5.1 µg/m³#36 Granby: 5.3 µg/m³#34 North Bay: 5.5 µg/m³#35 Vancouver: 5.5 µg/m³#32 Langley: 5.9 µg/m³#33 Richmond: 5.9 µg/m³#28 Alliston: 6.2 µg/m³#29 Burnaby: 6.2 µg/m³#30 Montréal: 6.2 µg/m³#31 Strawberry Hill: 6.2 µg/m³#27 Ottawa: 6.3 µg/m³#24 Delta: 6.4 µg/m³#25 Greater Sudbury: 6.4 µg/m³#26 Red Deer: 6.4 µg/m³#23 Trois-Rivières: 6.5 µg/m³#22 Kingston: 6.6 µg/m³#20 Barrie: 6.8 µg/m³#21 Edmonton: 6.8 µg/m³#19 Edmundston: 7.1 µg/m³#18 Abbotsford: 7.4 µg/m³#16 Brantford: 7.5 µg/m³#17 Saint-Georges: 7.5 µg/m³#15 St. Catharines: 7.6 µg/m³#14 Sept-Îles: 7.7 µg/m³#13 Belleville: 7.9 µg/m³#12 Waterdown: 8.2 µg/m³#10 London: 8.3 µg/m³#11 L'Ancienne-Lorette: 8.3 µg/m³#9 Québec: 8.4 µg/m³#8 Toronto: 9.0 µg/m³#7 Hamilton: 9.1 µg/m³#6 St. Thomas: 9.6 µg/m³#5 Gatineau: 10.5 µg/m³#4 Sarnia: 10.6 µg/m³#3 Windsor: 10.8 µg/m³#2 Shawinigan: 10.9 µg/m³#1 Nepean: 15.1 µg/m³
Each dot is a measured city, coloured by its PM2.5; tap a dot to open the city, or a region to zoom in.
← Nepean 15.1 WHO 24-hour guideline
Every measured city in Canada, one column each, worst on the left and cleanest on the right. Point at it to read a city; tap to open it.
  1. 1Nepeanlow-cost sensorsOntario 621.0×
  2. 2ShawiniganQuebec 540.7×
  3. 3WindsorOntario 540.7×
  4. 4SarniaOntario 540.7×
  5. 5Gatineaulow-cost sensorsQuebec 540.7×
  6. 6St. ThomasOntario 520.6×
  7. 7HamiltonOntario 510.6×
  8. 8TorontoOntario 500.6×
  9. 9QuébecQuebec 470.6×
  10. 10LondonOntario 460.6×
  11. 11L'Ancienne-LoretteQuebec 460.6×
  12. 12WaterdownOntario 460.5×
  13. 13BellevilleOntario 440.5×
  14. 14Sept-ÎlesQuebec 430.5×
  15. 15St. CatharinesOntario 420.5×
  16. 16BrantfordOntario 420.5×
  17. 17Saint-GeorgesQuebec 420.5×
  18. 18AbbotsfordBritish Columbia 410.5×
  19. 19EdmundstonNew Brunswick 390.5×
  20. 20BarrieOntario 380.5×
  21. 21EdmontonAlberta 380.5×
  22. 22KingstonOntario 370.4×
  23. 23Trois-RivièresQuebec 360.4×
  24. 24DeltaBritish Columbia 360.4×
  25. 25Greater SudburyOntario 360.4×
  26. 26Red DeerAlberta 360.4×
  27. 27OttawaOntario 350.4×
  28. 28AllistonOntario 340.4×
  29. 29BurnabyBritish Columbia 340.4×
  30. 30MontréalQuebec 340.4×
  31. 31Strawberry HillBritish Columbia 340.4×
  32. 32LangleyBritish Columbia 330.4×
  33. 33RichmondBritish Columbia 330.4×
  34. 34North BayOntario 310.4×
  35. 35VancouverBritish Columbia 310.4×
  36. 36GranbyQuebec 290.4×
  37. 37DrummondvilleQuebec 280.3×
  38. 38SaskatoonSaskatchewan 280.3×
  39. 39SherbrookeQuebec 270.3×
  40. 40ChilliwackBritish Columbia 260.3×
  41. 41MonctonNew Brunswick 260.3×
  42. 42Port CoquitlamBritish Columbia 260.3×
  43. 43Rouyn-NorandaQuebec 260.3×
  44. 44CalgaryAlberta 260.3×
  45. 45FrederictonNew Brunswick 260.3×
  46. 46Medicine HatAlberta 240.3×
  47. 47Swift CurrentSaskatchewan 240.3×
  48. 48Saint JohnNew Brunswick 240.3×
  49. 49CoquitlamBritish Columbia 230.3×
  50. 50AirdrieAlberta 220.3×
  51. 51DartmouthNova Scotia 210.2×
  52. 52West VancouverBritish Columbia 190.2×
  53. 53CharlottetownPrince Edward Island 160.2×
  54. 54Fort McMurrayAlberta 140.2×
  55. 55SydneyNova Scotia 130.2×
  56. 56MiltonOntario 120.1×
  57. 57St. AlbertAlberta 120.1×
  58. 58Prince AlbertSaskatchewan 100.1×
  59. 59Winnipeglow-cost sensorsManitoba 10.0×
  60. 60Yellowknifelow-cost sensorsNorthwest Territories 00.0×
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Estimated: cities without a monitor

Canada cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
Surrey≈ 6 µg/m³Good
Halifax≈ 4 µg/m³Good
Laval≈ 7 µg/m³Good
Etobicoke≈ 6 µg/m³Good
Markham≈ 4 µg/m³Good
Vaughan≈ 5 µg/m³Good
Longueuil≈ 7 µg/m³Good
Richmond Hill≈ 5 µg/m³Good
Burlington≈ 5 µg/m³Good
Oshawa≈ 5 µg/m³Good
Gloucester≈ 5 µg/m³Good
Rosemont–La Petite-Patrie≈ 7 µg/m³Good
Villeray–Saint-Michel–Parc-Extension≈ 7 µg/m³Good
Lévis≈ 8 µg/m³Good
Mercier–Hochelaga-Maisonneuve≈ 7 µg/m³Good
Whitby≈ 5 µg/m³Good
Cambridge≈ 5 µg/m³Good
Orléans≈ 4 µg/m³Good
Ottawa South≈ 5 µg/m³Good
Saint-Louis-de-Terrebonne≈ 7 µg/m³Good
Ajax≈ 5 µg/m³Good
Saanich≈ 4 µg/m³Good
Thornhill≈ 5 µg/m³Good
Terrebonne≈ 7 µg/m³Good
St. John's≈ 6 µg/m³Good
Thunder Bay≈ 4 µg/m³Good
Le Plateau-Mont-Royal≈ 7 µg/m³Good
Waterloo≈ 4 µg/m³Good
Ville-Marie≈ 7 µg/m³Good
Niagara Falls≈ 6 µg/m³Good
Pickering≈ 5 µg/m³Good
Kanata≈ 4 µg/m³Good
Montréal-Nord≈ 7 µg/m³Good
Le Sud-Ouest≈ 7 µg/m³Good
Repentigny≈ 7 µg/m³Good
Maple Ridge≈ 6 µg/m³Good
Willowdale≈ 5 µg/m³Good
New Westminster≈ 6 µg/m³Good
Caledon≈ 4 µg/m³Good
Stoney Creek≈ 5 µg/m³Good

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SmogRank, most polluted cities in Canada, PM2.5, last 24 hours to 2 Oct 2026, 02:00 UTC, smogrank.com/ca.

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Regions

Alberta 10British Columbia 27Manitoba 1New Brunswick 5Northwest Territories 1Nova Scotia 2Ontario 28Prince Edward Island 1Quebec 17Saskatchewan 3Yukon 1

Measured cities in each region (30 days).

Updated 2026-10-02 02:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.