SmogRank / Countries / Switzerland / September 2026

Most polluted cities in Switzerland, September 2026

5 cities in Switzerland ranked by their average PM2.5 over the 30 days. Worst: Bellinzona at 8.6 µg/m³, #533 of 2,332 cities in the world. Cleanest: Winterthur at 4.9. A city needs measurements on 70% of the days to be ranked.

  1. 1BellinzonaTicino
    8.6
  2. 2ZürichZurich
    6.5
  3. 3LuganoTicino
    6.0
  4. 4BaselBasel-City
    5.6
  5. 5Winterthurlow-cost sensorsZurich
    4.9
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

All cities in the world, September 2026 · Switzerland now