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.
- 1Nepeanlow-cost sensorsOntario 21.0×
- 2WindsorOntario 10.7×
- 3Gatineaulow-cost sensorsQuebec 10.7×
- 4SarniaOntario 10.7×
- 5ShawiniganQuebec 10.7×
- 6St. ThomasOntario 10.7×
- 7HamiltonOntario 10.6×
- 8TorontoOntario 10.6×
- 9LondonOntario 10.6×
- 10WaterdownOntario 10.6×
- 11QuébecQuebec 10.5×
- 12L'Ancienne-LoretteQuebec 10.5×
- 13BellevilleOntario 10.5×
- 14Sept-ÎlesQuebec 10.5×
- 15BrantfordOntario 10.5×
- 16St. CatharinesOntario 10.5×
- 17AbbotsfordBritish Columbia 10.5×
- 18Saint-GeorgesQuebec 10.5×
- 19EdmundstonNew Brunswick 10.5×
- 20EdmontonAlberta 10.5×
- 21KingstonOntario 10.5×
- 22BarrieOntario 10.4×
- 23Greater SudburyOntario 10.4×
- 24Trois-RivièresQuebec 10.4×
- 25DeltaBritish Columbia 10.4×
- 26MontréalQuebec 10.4×
- 27Red DeerAlberta 10.4×
- 28BurnabyBritish Columbia 10.4×
- 29OttawaOntario 10.4×
- 30Strawberry HillBritish Columbia 10.4×
- 31AllistonOntario 10.4×
- 32RichmondBritish Columbia 10.4×
- 33LangleyBritish Columbia 10.4×
- 34SaskatoonSaskatchewan 10.4×
- 35GranbyQuebec 10.4×
- 36VancouverBritish Columbia 10.4×
- 37North BayOntario 10.4×
- 38DrummondvilleQuebec 10.3×
- 39CalgaryAlberta 10.3×
- 40Rouyn-NorandaQuebec 10.3×
- 41SherbrookeQuebec 10.3×
- 42ChilliwackBritish Columbia 10.3×
- 43MonctonNew Brunswick 10.3×
- 44FrederictonNew Brunswick 10.3×
- 45Port CoquitlamBritish Columbia 10.3×
- 46Medicine HatAlberta 10.3×
- 47Swift CurrentSaskatchewan 10.3×
- 48CoquitlamBritish Columbia 10.3×
- 49Saint JohnNew Brunswick 10.3×
- 50AirdrieAlberta 10.3×
- 51DartmouthNova Scotia 10.2×
- 52West VancouverBritish Columbia 10.2×
- 53CharlottetownPrince Edward Island 10.2×
- 54Fort McMurrayAlberta 10.2×
- 55SydneyNova Scotia 10.2×
- 56St. AlbertAlberta 10.1×
- 57Prince AlbertSaskatchewan 10.1×
- 58MiltonOntario 10.1×
- 59Winnipeglow-cost sensorsManitoba 10.0×
- 60Yellowknifelow-cost sensorsNorthwest Territories 10.0×
The UK's Daily Air Quality Index (1 to 10), PM2.5 bands. 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.
| City | 7-day estimate |
|---|---|
| Surrey | ≈ 6 µg/m³ |
| Halifax | ≈ 4 µg/m³ |
| Laval | ≈ 7 µg/m³ |
| Etobicoke | ≈ 6 µg/m³ |
| Markham | ≈ 4 µg/m³ |
| Vaughan | ≈ 5 µg/m³ |
| Longueuil | ≈ 7 µg/m³ |
| Richmond Hill | ≈ 5 µg/m³ |
| Burlington | ≈ 5 µg/m³ |
| Oshawa | ≈ 5 µg/m³ |
| Gloucester | ≈ 5 µg/m³ |
| Rosemont–La Petite-Patrie | ≈ 7 µg/m³ |
| Villeray–Saint-Michel–Parc-Extension | ≈ 7 µg/m³ |
| Lévis | ≈ 8 µg/m³ |
| Mercier–Hochelaga-Maisonneuve | ≈ 7 µg/m³ |
| Whitby | ≈ 5 µg/m³ |
| Cambridge | ≈ 5 µg/m³ |
| Orléans | ≈ 4 µg/m³ |
| Ottawa South | ≈ 5 µg/m³ |
| Saint-Louis-de-Terrebonne | ≈ 7 µg/m³ |
| Ajax | ≈ 5 µg/m³ |
| Saanich | ≈ 4 µg/m³ |
| Thornhill | ≈ 5 µg/m³ |
| Terrebonne | ≈ 7 µg/m³ |
| St. John's | ≈ 6 µg/m³ |
| Thunder Bay | ≈ 4 µg/m³ |
| Le Plateau-Mont-Royal | ≈ 7 µg/m³ |
| Waterloo | ≈ 4 µg/m³ |
| Ville-Marie | ≈ 7 µg/m³ |
| Niagara Falls | ≈ 6 µg/m³ |
| Pickering | ≈ 5 µg/m³ |
| Kanata | ≈ 4 µg/m³ |
| Montréal-Nord | ≈ 7 µg/m³ |
| Le Sud-Ouest | ≈ 7 µg/m³ |
| Repentigny | ≈ 7 µg/m³ |
| Maple Ridge | ≈ 6 µg/m³ |
| Willowdale | ≈ 5 µg/m³ |
| New Westminster | ≈ 6 µg/m³ |
| Caledon | ≈ 4 µg/m³ |
| Stoney Creek | ≈ 5 µg/m³ |
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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 UK DAQI PM2.5 sub-index.