What is the air quality in Montreal?

Montreal, Canada has an annual US AQI of 46 (Reasonable) and average PM2.5 of 8.9 µg/m³, ranking #523 of 5856 cities. Main pollutant: PM2.5.

What is the cleanest month in Montreal?

October is typically the cleanest month (AQI 39) and February the most polluted (AQI 52).

PM2.5: 1997–2026 (monitors; 2025–2026 provisional). Measured by government monitoring stations. Full sources are on the methodology page.

Global rank	City	Continent	AQI	PM2.5
523	Montreal, Canada	North America	AQI 46	PM2.5 8.9 µg/m³