The TMB is a hiking trail, not a mountaineering route. But it crosses high mountains and three countries and passes through areas with no signal, so a few precautions are in order.
Emergency numbers
| Country | Number | Details |
|---|---|---|
| France | 112 | Free, and works even without a SIM card. Chamonix PGHM (mountain rescue gendarmerie): +33 4 50 53 16 89. |
| Italy | 112 | Single emergency number in the Aosta Valley, which alerts mountain rescue. 118 still works for medical emergencies. |
| Switzerland (Valais) | 144 | The whole Swiss section of the TMB is in Valais: 144 calls out the rescue team and helicopter (Air-Glaciers). 1414 (Rega) covers the rest of Switzerland. |
Mountain distress signal: six signals a minute (with a whistle or a light), a one-minute pause, then repeat.
Do you have to pay for rescue?
- France: mountain rescue is free.
- Switzerland: you pay. An average helicopter rescue cost around CHF 3,800 in 2022; flying time in a twin-engine helicopter is billed at more than CHF 100 per minute.
- Italy (Aosta Valley): partly chargeable, especially if the call-out is deemed unjustified.
Take out insurance covering search, rescue and helicopter evacuation in Switzerland and Italy (the insurance that comes with a premium bank card, an alpine club or FFRandonnée licence, or a dedicated policy; the official platform offers one at €2.75 per day).
Documents and borders
Citizens of the European Union and EFTA can travel with a valid identity card or passport. Switzerland is still a customs border: the duty-free allowance on purchases is CHF 150 per person per day. Also bring your European Health Insurance Card (EHIC).
Phone and mobile signal
Switzerland is not in the European Union, so roaming depends on your mobile plan. Check before you leave whether Switzerland is included; if not, turn off mobile data. Don’t count on having signal on the passes or in some hamlets such as Les Chapieux.
Good habits
- Check the weather every evening and set off early so you cross the passes before the storms.
- Let your accommodation know if you won’t be coming or will be arriving late.
- Carry a topographic map, a head torch, an emergency blanket and a small first-aid kit.
- Don’t attempt a high variant (Col des Fours, Fenêtre d’Arpette, Mont de la Saxe) when the weather is uncertain or there is snow.
Other guides
- How to book TMB huts for 2027: a step-by-step guide
- TMB 2027 rules: compulsory booking and no more wild camping?
- Tour du Mont Blanc budget: how much does the TMB cost?
- Getting to and around the TMB: trains, buses and lifts
- Wild camping on the TMB: bivouac and campsite rules by country
- Best time to hike the Tour du Mont Blanc: seasons and weather
- Tour du Mont Blanc packing list: the complete checklist
- Training for the Tour du Mont Blanc: fitness and 8-week plan