How to correctly calculate an employee's vacation days
Learn how to calculate vacation days correctly, avoid common mistakes and automate the process with HR software.

Calculating vacation days is one of the administrative tasks that raises the most questions in any HR department. Mid-year hires, reduced working hours, collective agreements and different ways of counting days can turn a seemingly simple calculation into a source of errors.
Calendar days or working days
Spain's Workers' Statute sets a minimum of 30 calendar days per year, although many collective agreements convert that entitlement into working days. Before doing any calculation, it's essential to check which criterion applies in the company.
How to calculate prorated vacation days
When an employee doesn't work the full year, vacation must be calculated in proportion to the time actually worked. Tracking this in spreadsheets can lead to errors, especially when there are changes in working hours or temporary contracts.
Most common mistakes
- Mixing calendar days and working days.
- Not updating the balance after each approved request.
- Not accounting for changes in working hours or seniority.
- Managing the calculation manually for the whole workforce.
Best practices
Automating the calculation reduces errors, improves transparency for employees and prevents disputes later on. A specialized platform lets you check the available balance in real time and keeps a full history of requests.
Frequently asked questions
How many vacation days are legally required in Spain?
Spain's Workers' Statute sets a minimum of 30 calendar days per year worked, unless the applicable collective agreement grants more or expresses it in working days.
How are vacation days calculated when an employee joins mid-year?
They are calculated in proportion to time worked: the annual total is divided by 12 months and multiplied by the months worked up to the calculation date.
What happens if an employee is on sick leave during their vacation?
The vacation is interrupted and the employee is entitled to take it at another time, as long as no more than 18 months have passed since the end of the year it was accrued in.
Can the company set vacation dates unilaterally?
No. The vacation schedule must be agreed between company and employee, and must be known at least two months before the dates taken.

