Part time work and principle of prorata temporis

By its decision of November 11th 2015 , the European Court of Justice (hereinafter the “ECJ”) ruled that the periods during which a part-time employee had increased his working time should be taken into account, pro rata, for the calculation of his/her right to paid leave.

For this purpose, the ECJ stated that in the event of an increase in the number of hours of work performed by an employee, the Member States are not obliged to provide that the entitlement to paid annual leave already accrued, and possibly taken, must be recalculated retroactively according to that employee’s new work pattern. A new calculation must, however, be performed for the period during which working time increased.