EU (& EEA) & Swiss employees of Geneva entities who live in France can, since 1 July 2023, spend up to 40% of their work time from home (the framework agreement can be reviewed here). If they exceed this limit there will be a need to register for not only French social security contributions for that time spent working in France, but also for French tax. This provision also applies to British citizens who worked in Switzerland before 1 January 2021 and have continued to work there since.
For those employees working less than 25% of the work time from home no further measures need to be taken at this stage. For those employees who work up to 40% from home it is necessary to fill out the ALPS declaration form. It will be necessary to provide additional information confirming the health insurance status of the employee, as well as nationality and some other personal details. These notifications are then valid for up to 3 years. Normally the application should be made within 3 months of an employee starting to work.
It should also be noted that persons who have multiple employers will most often not be covered by these provisions.
The Geneva tax authorities are also informing employers that it will be necessary to start keeping records of the time border workers (typically, workers living in France, but having their place of employment in Geneva) spend working from home. This necessity would begin in 2025, and employers would need to provide this information early in the following year (so for the first time in early 2026).