Most polluted cities in Canada

95 measured cities ranked by PM2.5, last 7 days. Worst: Calgary at 7.6 µg/m³, #1058 in the world.

#	City	µg/m³
1	Calgary Alberta	7.6
2	Red Deer Alberta	7.3
3	Saint-Jean-sur-Richelieu Quebec	7.0
4	Barrie Ontario	6.9
5	Newmarket Ontario	6.5
6	Saskatoon Saskatchewan	6.4
7	Vernon British Columbia	6.4
8	L'Ancienne-Lorette Quebec	6.4
9	Chilliwack British Columbia	6.3
10	Brossard Quebec	6.2
11	Cornwall Ontario	6.1
12	Edmonton Alberta	6.1
13	Greater Sudbury Ontario	6.1
14	London Ontario	6.1
15	Montréal Quebec	6.1
16	Brantford Ontario	6.0
17	Toronto Ontario	6.0
18	Québec Quebec	6.0
19	Kelowna British Columbia	5.9
20	Sept-Îles Quebec	5.8
21	Shawinigan Quebec	5.8
22	Airdrie Alberta	5.7
23	Regina Saskatchewan	5.7
24	Sorel-Tracy Quebec	5.7
25	Trois-Rivières Quebec	5.7
26	Rivière-des-Prairies–Pointe-aux-Trembles Quebec	5.7
27	Lethbridge Alberta	5.6
28	St. Catharines Ontario	5.6
29	Hamilton Ontario	5.5
30	Kitchener Ontario	5.3
31	St. Thomas Ontario	5.3
32	Windsor Ontario	5.3
33	Guelph Ontario	5.2
34	Milton Ontario	5.2
35	Oakville Ontario	5.2
36	Brampton Ontario	5.1
37	Drummondville Quebec	5.1
38	Saint-Georges Quebec	5.1
39	Granby Quebec	5.0
40	Nepean low-cost sensorsOntario	5.0
41	Rouyn-Noranda Quebec	5.0
42	Waterdown Ontario	5.0
43	North Bay Ontario	4.9
44	Sarnia Ontario	4.9
45	Swift Current Saskatchewan	4.9
46	Kamloops British Columbia	4.8
47	Mississauga Ontario	4.8
48	Saguenay Quebec	4.8
49	Edmundston New Brunswick	4.8
50	Abbotsford British Columbia	4.6
51	Victoria British Columbia	4.6
52	Belleville Ontario	4.5
53	Kingston Ontario	4.4
54	Sherwood Park Alberta	4.4
55	Vancouver British Columbia	4.4
56	Langford British Columbia	4.3
57	Langley British Columbia	4.3
58	Medicine Hat Alberta	4.3
59	Richmond British Columbia	4.3
60	Strawberry Hill British Columbia	4.3
61	Chatham Ontario	4.2
62	Delta British Columbia	4.2
63	Campbell River British Columbia	4.1
64	Ottawa Ontario	4.1
65	Sherbrooke Quebec	4.1
66	Duncan British Columbia	4.0
67	Burnaby British Columbia	3.9
68	Alliston Ontario	3.8
69	Coquitlam British Columbia	3.8
70	Cranbrook British Columbia	3.8
71	Peterborough Ontario	3.8
72	Squamish British Columbia	3.8
73	Moncton New Brunswick	3.7
74	Port Coquitlam British Columbia	3.7
75	St. Albert Alberta	3.7
76	Miramichi New Brunswick	3.6
77	North Vancouver British Columbia	3.5
78	Prince George British Columbia	3.5
79	Sault Ste. Marie Ontario	3.5
80	Fredericton New Brunswick	3.4
81	Saint John New Brunswick	3.4
82	Charlottetown Prince Edward Island	3.3
83	Nanaimo British Columbia	3.3
84	Terrace British Columbia	3.3
85	Winnipeg low-cost sensorsManitoba	3.3
86	Dartmouth Nova Scotia	2.9
87	Gatineau low-cost sensorsQuebec	2.9
88	West Vancouver British Columbia	2.9
89	Port Alberni British Columbia	2.7
90	Fort McMurray Alberta	2.3
91	Whitehorse Yukon	2.1
92	Grande Prairie Alberta	2.0
93	North Cowichan British Columbia	2.0
94	Fort St. John British Columbia	1.9
95	Yellowknife low-cost sensorsNorthwest Territories	0.1

Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data

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	Band
Surrey estimated	≈ 6 µg/m³	Good
Halifax estimated	≈ 4 µg/m³	Good
Laval estimated	≈ 7 µg/m³	Good
Etobicoke estimated	≈ 6 µg/m³	Good
Markham estimated	≈ 4 µg/m³	Good
Vaughan estimated	≈ 5 µg/m³	Good
Longueuil estimated	≈ 7 µg/m³	Good
Richmond Hill estimated	≈ 5 µg/m³	Good
Burlington estimated	≈ 5 µg/m³	Good
Oshawa estimated	≈ 5 µg/m³	Good
Gloucester estimated	≈ 5 µg/m³	Good
Rosemont–La Petite-Patrie estimated	≈ 7 µg/m³	Good
Villeray–Saint-Michel–Parc-Extension estimated	≈ 7 µg/m³	Good
Lévis estimated	≈ 8 µg/m³	Good
Mercier–Hochelaga-Maisonneuve estimated	≈ 7 µg/m³	Good
Whitby estimated	≈ 5 µg/m³	Good
Cambridge estimated	≈ 5 µg/m³	Good
Orléans estimated	≈ 4 µg/m³	Good
Ottawa South estimated	≈ 5 µg/m³	Good
Saint-Louis-de-Terrebonne estimated	≈ 7 µg/m³	Good
Ajax estimated	≈ 5 µg/m³	Good
Saanich estimated	≈ 4 µg/m³	Good
Thornhill estimated	≈ 5 µg/m³	Good
Terrebonne estimated	≈ 7 µg/m³	Good
St. John's estimated	≈ 6 µg/m³	Good
Thunder Bay estimated	≈ 5 µg/m³	Good
Le Plateau-Mont-Royal estimated	≈ 7 µg/m³	Good
Waterloo estimated	≈ 4 µg/m³	Good
Ville-Marie estimated	≈ 7 µg/m³	Good
Niagara Falls estimated	≈ 6 µg/m³	Good
Pickering estimated	≈ 5 µg/m³	Good
Kanata estimated	≈ 4 µg/m³	Good
Montréal-Nord estimated	≈ 7 µg/m³	Good
Le Sud-Ouest estimated	≈ 7 µg/m³	Good
Repentigny estimated	≈ 7 µg/m³	Good
Maple Ridge estimated	≈ 6 µg/m³	Good
Willowdale estimated	≈ 5 µg/m³	Good
New Westminster estimated	≈ 6 µg/m³	Good
Caledon estimated	≈ 4 µg/m³	Good
Stoney Creek estimated	≈ 5 µg/m³	Good

Regions

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

Updated 2026-10-01 07:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.