Updated November 2026
The short answer: yes, you still need sun protection in winter. UVB (the burning rays) drops a lot in the darker months, but UVA (the ageing rays) drops far less. It passes through clouds and window glass. In the snow and the mountains, your UV exposure can be higher than on a summer day in town.
UVA vs UVB: what changes in winter?
About 95% of the UV radiation that reaches the ground is UVA. The rest is UVB.
- UVB causes sunburn and depends strongly on how high the sun is. In a Swiss winter, the lowland UV index is often just 1 or 2, so sunburn in town is unlikely.
- UVA varies much less with the seasons and the weather. It reaches deeper into the skin, into the dermis, where it breaks down collagen and elastin and triggers pigmentation. You don't feel it, and the damage shows years later as wrinkles, loss of firmness and dark spots.
- Window glass blocks most UVB but lets much of the UVA through. Car windscreens filter most UVA; side windows often don't. That's why people who drive a lot often show more sun damage on one side of the face.
So a winter day by the window, on your commute or on a walk still adds UVA, day after day.
Snow and altitude: why winter sport needs SPF 50
For anyone skiing, snowboarding or hiking in the Alps, winter is a high-UV season:
- Snow reflects up to 80% of UV radiation (WHO), so you get UV from above and from below. Grass or soil reflects only a few percent.
- UV rises by about 10% for every 1,000 metres of altitude. At 2,500 m, that's roughly 25% more than at lake level, before counting the snow.
- Cold air and wind hide the warmth of the sun, so you don't notice the exposure until your skin is already red.
On the slopes, use SPF 50 on all exposed skin and reapply about every two hours, and after sweating or wiping your face. Don't forget the areas reflected light reaches: under the chin, the nose, the ears and the lips.
What UVA does to your skin over time
UVA damage builds up quietly. Over the years it contributes to:
- Fine lines and wrinkles
- Loss of firmness
- Uneven skin tone and dark spots (hyperpigmentation, melasma)
- Oxidative stress: UVA creates free radicals in the skin, which damage cells
Read more about how this works in Sun and skin ageing: how UV causes wrinkles and spots.
A simple winter routine
- Cleanse gently. Cold air and heating dry the skin out, so skip harsh cleansers.
- Moisturise and protect. The Daily Protection Hydrating Day Cream SPF 30 hydrates and adds broad-spectrum protection for everyday winter days in town.
- Add tinted SPF 50. The Daily Protection Liquid Foundation SPF 50+ gives light coverage and high protection in one step, with niacinamide to help keep skin calm.
- Top up with powder. The Mineral Loose Powder SPF 50+ lets you refresh your protection over makeup, for example at lunch on the slopes, without starting again.
Use enough product: about a teaspoon for the face and neck. Here's how much sunscreen your face really needs.
Winter sun protection: frequently asked questions
Do I need sunscreen in winter if I'm mostly indoors?
If you sit by a window or go outside during the day, yes. A day cream or foundation with broad-spectrum SPF is usually enough for an ordinary winter day in town, as long as you apply enough of it.
Is SPF 30 enough in winter?
For everyday life in the lowlands, a broad-spectrum SPF 30 is fine. For skiing, snowshoeing or a day in the mountains, choose SPF 50 and reapply. More on SPF 30 vs SPF 50.
Can you get sunburned in winter?
Yes, especially at altitude and on snow. Sunburn on the slopes is common because the cold hides the warning signs.
Does sunscreen stop me getting vitamin D in winter?
In Switzerland, the sun is too low from roughly October to March for the skin to make much vitamin D anyway, with or without sunscreen. Many people get it from food or supplements in those months. See everything you need to know about vitamin D, and ask your doctor what's right for you.
Conclusion
Winter changes the kind of sun, not the need for protection. UVA reaches your skin all year, and snow and altitude make winter days in the mountains some of the most intense of the year. A daily SPF in your routine, plus SPF 50 and reapplying when you're on the slopes, keeps your skin protected through every season.
