SmogRank / Countries / Switzerland / October 2025

Most polluted cities in Switzerland, October 2025

6 cities in Switzerland ranked by their average PM2.5 over the 31 days. Worst: Winterthur at 12.4 µg/m³, #311 of 2,110 cities in the world. Cleanest: Zürich at 6.1. A city needs measurements on 70% of the days to be ranked.

  1. 1Winterthurlow-cost sensorsZurich
    12.4
  2. 2LuganoTicino
    12.2
  3. 3BellinzonaTicino
    11.3
  4. 4BernBern
    8.0
  5. 5BaselBasel-City
    6.6
  6. 6ZürichZurich
    6.1
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, October 2025 · Switzerland now