In the second half of 2026, from September through December, the Mont Blanc Tunnel will be closed several times, and vehicle traffic will be prohibited in both directions. Most of the closures will take place at night, between 10 p.m. and 6 a.m., during which time important maintenance work will be carried out.
In September, drivers can expect two periods of tunnel closures:
- On the nights of September 14–15, 15–16, 16–17, and 17–18, from 10 p.m. to 6 a.m.
- On the nights of September 21–22, 22–23, 23–24, and 24–25, from 10 p.m. to 6 a.m.
Three tunnel closure periods are scheduled for October:
- On the nights of October 5–6, 6–7, 7–8, and 8–9, from 10 p.m. to 6 a.m.
- On the night of October 12–13, from 7 p.m. to 6 a.m., and on the nights of October 13–14, 14–15, and 15–16, from 10 p.m. to 6 a.m.
- On the nights of October 19–20, 20–21, 21–22, 22–23, 26–27, 27–28, 28–29, and 29–30, from 10 p.m. to 6 a.m.
In November, just as in September, there will be two periods when the tunnel will be closed:
- On the nights of November 2–3, 3–4, 4–5, and 5–6, from 10 p.m. to 6 a.m.
- On the nights of November 16–17, 17–18, 18–19, and 19–20, from 10 p.m. to 6 a.m.
Additionally, in November, the tunnel will be closed for 12 hours from 6 p.m. on the 24th to 6 a.m. on the 25th.
The final tunnel closures of the year in December will take place on the nights of December 14–15, 15–16, 16–17, and 17–18, from 10 p.m. to 6 a.m.