Passengers are being told to prepare for trains leaving at different times and from different platforms than they are used to, starting on December 13th.
Swiss Federal Railways (SBB) has posted information on its website detailing the changes that will be particularly marked in the Zurich region and in Western Switzerland.
“Roughly, 80 percent of the schedules are going to change in Suisse Romande (French-speaking Switzerland),” an SBB regional coordinator warned earlier this year.
In addition to the information on its website, SBB is making available 350 staff to help travellers familiarize themselves with the new timetable.
And it will be setting up information booths at stations to offer further help.
The changes are being driven by the addition of a recently opened station underneath the main Zurich train station, as well as the launch of Léman 2030, a three-billion-franc expansion project between Geneva and Lausanne to be carried out over the next ten years.
The new Zurich station will allow for more routes to be added to the local S-bahn network and quicker cross-country connections using the new diameter line.
SBB earlier noted that trips from Geneva in the west of the country to Saint Gallen in the northeast will be cut by 18 minutes, bringing the fastest connections to three hours and 46 minutes.
In many regions more rush-hour trains will be available but work to upgrade Lausanne's station will have a negative impact on service in French-speaking Switzerland.
The west wing of the station will be closed for renovations, including the buffet de la gare restaurant, which first opened in 2016.
Trains between Geneva and Lausanne will take three minutes longer, while reductions in service are planned between Lausanne and the canton of Valais.
Over the longer term, the Léman 2030 project will double the capacity of passenger trains between Geneva and Lausanne.
In the Jura, direct trains to Geneva will be eliminated under the new schedule in favour of liaisons via Biel/Bienne, while half-hourly service will replace trains once an hour from Neuchâtel to La Chaux-de-Fonds.