“All UK nationals travelling to Switzerland must have a UK passport with at least 6 months validity – the 6 month passport validity upon entry is NOT mandatory for holders of a Swiss residence permit.
UK nationals without residency in Switzerland do not need a visa, as long as they are not staying longer than 90 days per 180 days. If helpful, a travel time calculator for Switzerland and the EU can be found at:
https://www.sem.admin.ch/sem/en/home/themen/einreise/aufenthaltsrechner.html
If you have a B, C, G or L permit for Switzerland, you are exempt from the 90/180 days limit in Switzerland. When entering or leaving Switzerland or an EU country, you must present your Swiss residence permit along with your passport. If you are travelling within the EU and are a sole UK passport holder with residence rights in Switzerland, there is still a 90 day per 180 day limit within the EU.
The Embassy cannot advise on taxation issues between Switzerland and other EU states. All UK nationals who own property in Switzerland and/or neighbouring countries will have to adhere to the local taxation regulations as laid down by the authorities in those countries concerned.”
British Embassy Berne