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 15.6 µg/m³, #109 in the world.

Quebec: 17 measured citiesSaskatchewan: 3 measured citiesYukonNorthwest 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 Milton: 1.8 µg/m³#57 Prince Albert: 1.9 µg/m³#56 St. Albert: 2.2 µg/m³#55 Sydney: 2.3 µg/m³#54 Fort McMurray: 2.7 µg/m³#53 Charlottetown: 3.0 µg/m³#52 West Vancouver: 3.4 µg/m³#51 Dartmouth: 3.7 µg/m³#50 Airdrie: 4.0 µg/m³#48 Coquitlam: 4.2 µg/m³#49 Saint John: 4.2 µg/m³#46 Medicine Hat: 4.5 µg/m³#47 Swift Current: 4.5 µg/m³#44 Fredericton: 4.6 µg/m³#45 Port Coquitlam: 4.6 µg/m³#42 Chilliwack: 4.7 µg/m³#43 Moncton: 4.7 µg/m³#39 Calgary: 4.8 µg/m³#40 Rouyn-Noranda: 4.8 µg/m³#41 Sherbrooke: 4.8 µg/m³#38 Drummondville: 5.1 µg/m³#37 North Bay: 5.3 µg/m³#35 Granby: 5.5 µg/m³#36 Vancouver: 5.5 µg/m³#33 Langley: 5.8 µg/m³#34 Saskatoon: 5.8 µg/m³#32 Richmond: 5.9 µg/m³#31 Alliston: 6.0 µg/m³#30 Strawberry Hill: 6.2 µg/m³#28 Burnaby: 6.3 µg/m³#29 Ottawa: 6.3 µg/m³#25 Delta: 6.4 µg/m³#26 Montréal: 6.4 µg/m³#27 Red Deer: 6.4 µg/m³#22 Barrie: 6.5 µg/m³#23 Greater Sudbury: 6.5 µg/m³#24 Trois-Rivières: 6.5 µg/m³#20 Edmonton: 6.8 µg/m³#21 Kingston: 6.8 µg/m³#19 Edmundston: 7.1 µg/m³#18 Saint-Georges: 7.3 µg/m³#17 Abbotsford: 7.4 µg/m³#15 Brantford: 7.9 µg/m³#16 St. Catharines: 7.9 µg/m³#13 Belleville: 8.0 µg/m³#14 Sept-Îles: 8.0 µg/m³#11 Québec: 8.1 µg/m³#12 L'Ancienne-Lorette: 8.1 µg/m³#9 London: 8.6 µg/m³#10 Waterdown: 8.6 µg/m³#8 Toronto: 9.3 µg/m³#7 Hamilton: 9.5 µg/m³#6 St. Thomas: 10.0 µg/m³#3 Gatineau: 10.9 µg/m³#4 Sarnia: 10.9 µg/m³#5 Shawinigan: 10.9 µg/m³#2 Windsor: 11.1 µg/m³#1 Nepean: 15.6 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 15.6 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 231.0×
  2. 2WindsorOntario 160.7×
  3. 3Gatineaulow-cost sensorsQuebec 160.7×
  4. 4SarniaOntario 160.7×
  5. 5ShawiniganQuebec 160.7×
  6. 6St. ThomasOntario 150.7×
  7. 7HamiltonOntario 140.6×
  8. 8TorontoOntario 140.6×
  9. 9LondonOntario 130.6×
  10. 10WaterdownOntario 130.6×
  11. 11QuébecQuebec 120.5×
  12. 12L'Ancienne-LoretteQuebec 120.5×
  13. 13BellevilleOntario 120.5×
  14. 14Sept-ÎlesQuebec 120.5×
  15. 15BrantfordOntario 120.5×
  16. 16St. CatharinesOntario 120.5×
  17. 17AbbotsfordBritish Columbia 110.5×
  18. 18Saint-GeorgesQuebec 110.5×
  19. 19EdmundstonNew Brunswick 110.5×
  20. 20EdmontonAlberta 100.5×
  21. 21KingstonOntario 100.5×
  22. 22BarrieOntario 100.4×
  23. 23Greater SudburyOntario 100.4×
  24. 24Trois-RivièresQuebec 100.4×
  25. 25DeltaBritish Columbia 100.4×
  26. 26MontréalQuebec 100.4×
  27. 27Red DeerAlberta 100.4×
  28. 28BurnabyBritish Columbia 90.4×
  29. 29OttawaOntario 90.4×
  30. 30Strawberry HillBritish Columbia 90.4×
  31. 31AllistonOntario 90.4×
  32. 32RichmondBritish Columbia 90.4×
  33. 33LangleyBritish Columbia 90.4×
  34. 34SaskatoonSaskatchewan 90.4×
  35. 35GranbyQuebec 80.4×
  36. 36VancouverBritish Columbia 80.4×
  37. 37North BayOntario 80.4×
  38. 38DrummondvilleQuebec 80.3×
  39. 39CalgaryAlberta 70.3×
  40. 40Rouyn-NorandaQuebec 70.3×
  41. 41SherbrookeQuebec 70.3×
  42. 42ChilliwackBritish Columbia 70.3×
  43. 43MonctonNew Brunswick 70.3×
  44. 44FrederictonNew Brunswick 70.3×
  45. 45Port CoquitlamBritish Columbia 70.3×
  46. 46Medicine HatAlberta 70.3×
  47. 47Swift CurrentSaskatchewan 70.3×
  48. 48CoquitlamBritish Columbia 60.3×
  49. 49Saint JohnNew Brunswick 60.3×
  50. 50AirdrieAlberta 60.3×
  51. 51DartmouthNova Scotia 60.2×
  52. 52West VancouverBritish Columbia 50.2×
  53. 53CharlottetownPrince Edward Island 50.2×
  54. 54Fort McMurrayAlberta 40.2×
  55. 55SydneyNova Scotia 40.2×
  56. 56St. AlbertAlberta 40.1×
  57. 57Prince AlbertSaskatchewan 30.1×
  58. 58MiltonOntario 30.1×
  59. 59Winnipeglow-cost sensorsManitoba 10.0×
  60. 60Yellowknifelow-cost sensorsNorthwest Territories 00.0×
Excellent0–50
Good51–100
Lightly polluted101–150
Moderately polluted151–200
Heavily polluted201–300
Severely polluted301+

China's Air Quality Index (HJ 633-2012), PM2.5 individual index. 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/m³Excellent
Halifax≈ 4 µg/m³Excellent
Laval≈ 7 µg/m³Excellent
Etobicoke≈ 6 µg/m³Excellent
Markham≈ 4 µg/m³Excellent
Vaughan≈ 5 µg/m³Excellent
Longueuil≈ 7 µg/m³Excellent
Richmond Hill≈ 5 µg/m³Excellent
Burlington≈ 5 µg/m³Excellent
Oshawa≈ 5 µg/m³Excellent
Gloucester≈ 5 µg/m³Excellent
Rosemont–La Petite-Patrie≈ 7 µg/m³Excellent
Villeray–Saint-Michel–Parc-Extension≈ 7 µg/m³Excellent
Lévis≈ 8 µg/m³Excellent
Mercier–Hochelaga-Maisonneuve≈ 7 µg/m³Excellent
Whitby≈ 5 µg/m³Excellent
Cambridge≈ 5 µg/m³Excellent
Orléans≈ 4 µg/m³Excellent
Ottawa South≈ 5 µg/m³Excellent
Saint-Louis-de-Terrebonne≈ 7 µg/m³Excellent
Ajax≈ 5 µg/m³Excellent
Saanich≈ 4 µg/m³Excellent
Thornhill≈ 5 µg/m³Excellent
Terrebonne≈ 7 µg/m³Excellent
St. John's≈ 6 µg/m³Excellent
Thunder Bay≈ 4 µg/m³Excellent
Le Plateau-Mont-Royal≈ 7 µg/m³Excellent
Waterloo≈ 4 µg/m³Excellent
Ville-Marie≈ 7 µg/m³Excellent
Niagara Falls≈ 6 µg/m³Excellent
Pickering≈ 5 µg/m³Excellent
Kanata≈ 4 µg/m³Excellent
Montréal-Nord≈ 7 µg/m³Excellent
Le Sud-Ouest≈ 7 µg/m³Excellent
Repentigny≈ 7 µg/m³Excellent
Maple Ridge≈ 6 µg/m³Excellent
Willowdale≈ 5 µg/m³Excellent
New Westminster≈ 6 µg/m³Excellent
Caledon≈ 4 µg/m³Excellent
Stoney Creek≈ 5 µg/m³Excellent

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SmogRank, most polluted cities in Canada, PM2.5, last 24 hours to 2 Oct 2026, 03:00 UTC, smogrank.com/ca.

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Regions

Measured cities in each region (30 days).

Updated 2026-10-02 03:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the China AQI PM2.5 sub-index.