Weather
Although September is the first month of fall in Switzerland, the weather is generally quite summery, with pleasant temperatures ideal for getting outdoors. Temperatures vary by altitude, but the lower-lying cities will mostly be mild-to-warm in September, particularly earlier. The average September temperature in Geneva, Lugano, and Zürich is around 67°F (19°C), which is a few degrees cooler than in July and August. In Zermatt, in the high-altitude Alps, the average September temperature is 45°F (7°C), which is not much different from early summer averages.
Crowds & Costs
After a busy summer season, September is the start of the low season. But this has more to do with European (and other) travelers going back to work and school after their summer vacation than the conditions in Switzerland itself, which are still great for travel. If you can visit Switzerland in September rather than in the summer, you should consider doing so. There will be fewer other tourists, so hiking trails will be uncrowded, your first choice of hotel will be available, and you might even get discounted rates on flights and accommodation.
One thing to note is that some mountain huts and facilities, especially at higher elevations, may close for the season as early as mid-September.
Where to Go
Switzerland's mountain hiking trails are popular throughout the summer, but some travelers say September is the best time for hiking. Unlike early in the summer, there's little risk of lingering snow on the ground, and the general absence of too many other travelers makes for a more peaceful experience. The gold and red hues of the trees' changing colors are an added bonus.
Head to Valais to combine hiking with another of September's highlights: wine tasting (see more below). The Chemin du Vignoble trail is a 41-mile (66-km) trail that passes through Switzerland's most prominent wine region. The whole trek takes around four days, but you can break this into smaller sections. The route between Sion and Sierre, for example, can be done in one reasonably leisurely day of hiking, and this is sometimes said to be the most attractive section of the whole hike.
Read Eight Best Day Hikes in Switzerland for more information on hiking in Switzerland.
Chat with a local specialist who can help organize your trip.
What to Do
Like its neighbors, Italy and France, Switzerland produces many fine wines. The best times to sample Swiss wines are during the Caves Ouvertes when winemakers open up in spring and fall and offer tastings for a reduced fee. Visit one or more of Switzerland's wine regions to sample wine, hike, bike, or take a scenic train ride through wine country. The six regions are Geneva, German-speaking Switzerland, Three Lakes (including Neuchatel, Fribourg, and part of the canton of Bern), Ticino, Vaud, and Valais.
One of these scenic train rides that's highly worth boarding whether you're into wine or not is the Lavaux Express, a toy train pulled by a tractor. It trundles through the UNESCO-listed Lavaux vineyards, terraced and sloping directly into Lake Geneva. The train runs a few times a day until October and includes stops at wine-making villages.
Check out Switzerland's Best Train Rides for alternate options.
Events in September
La Désalpe de Charmey, Charmey. The Alpine village of Charmey, near Gruyères, is the setting for one of the most famous traditional festivals in the Swiss mountains, which celebrates the descent of the cows from their summer grazing high in the pastures. Expect music, dancing, and traditional food.
Jeûne Genevois, Geneva. Geneva's thanksgiving day is held on the Thursday following the first Sunday of September and is a public holiday in this canton.
Federal Day of Thanksgiving, Repentance, and Prayer, nationwide except Geneva. This interfaith festival is a public holiday on the third Sunday in September (except Geneva Canton).
Festivity of Autumn, Lugano. Over three days at the end of September and/or the start of October, the city of Lugano puts on a display and celebration of Ticino's music, food, and drink.
Traveling to Switzerland in September? Check out these great itineraries
Exploring the Wine Regions of Mont Blanc - 6 Days. Sample some of the world's best wines as you circle Mont Blanc from Switzerland to Italy to France. Visit vineyards nestled in the idyllic countryside in the foothills of the Alps, where ancient grape varieties still produce rare and high-quality wines.
Chamonix to Zermatt Walker's Haute Route - 8 Days. Experience the best of the Swiss Alps on this trek from the Valais Valley to Zermatt. From traditional alpine villages to high rocky passes, you'll hike along glacier foothills, traverse mountainsides, and trek through alpine meadows and peaceful lakeshores.
More Helpful Information
Switzerland in August
Switzerland in October
Best Time of Year to Visit Switzerland
How Many Days to Spend in Switzerland