Starting January 1, 2024, the customs tariff in Switzerland will be adjusted to remove the customs duties and simplify the customs tariff structure of most industrial products.
Proof of origin will not be needed at the time of importation if it is known that the goods will remain or be consumed in Switzerland.
The announcement of the tariff changes can be found here:
https://www.bazg.admin.ch/bazg/fr/home/services/services-entreprises/services-firmen_einfuhr-ausfuhr-durchfuhr/zolltarif-tares/aufhebung-der-industriezoelle.html