Employees who performed their work in their home country due to COVID-19 restrictions can deem to have these work-days performed in the country where they usually perform their work ("deemed work-days"). Employees are required to prove that such deemed work-days were subjected to tax by the work country at ordinary rates. In addition, they will need to notify the relevant tax authorities in their home country as well as their employers providing suitable evidence (e.g., number of days spent in the home country that would have been spent in the work country without COVID-19).
The employer will have to certify the application of the deemed work-days rule (e.g., on the salary certificate or other suitable format).
Where employees make use of the deemed work-day rule, they agree that the work country will tax the relevant income. Please note that the deemed work-days rule is not applicable for work-days that would have been spent in the home country anyway (e.g., according to the employment contract).
Where employees do not make use of the deemed work-days rule, the existing rules of the Switzerland-Germany tax treaty continue to apply. However, employment income paid to employees that were unable to work, will be taxable in the country where they ordinarily would have worked (reference period is the calendar year 2019).