Seniority at work begins from the first day that the employee provides services to the company. Seniority is the time that the employee has provided services to a certain company without interruption .
What is seniority for?
Seniority is taken into account not only when calculating severance pay (the longer you have worked, the more compensation you are entitled to receive), but it is also important in other cases, for example:
Seniority bonus : the employee receives a bonus for having worked rich people database for a certain amount of time in the company. Both the amount and the calculation are recognised in the Collective Agreement.
If you want to request a voluntary leave of absence , you must have at least one year of seniority.
Promotions : the company must take into account the seniority of the worker, among other requirements .
Transfers: those workers with the most seniority have preference not to be transferred .
The employee's seniority is maintained even if there is a company subrogation. The employee maintains all of the rights he had before the subrogation, including seniority.
If a worker has signed several temporary contracts, i.e. concatenated temporary contracts, the calculation of seniority begins with the start of the first contract .

The Supreme Court's case law establishes that seniority in the job counts for all time worked in the company, even if it was under different temporary employment contracts (including work in a Temporary Employment Agency) unless there are significant interruptions between said contracts.
As long as there is no breach of the essential unity of the contractual relationship , the employment relationship is understood to be the same.
«Seniority is a right of the worker and he cannot renounce it.»
Amount of seniority
Article 25 of the Workers' Statute provides a generic regulation of the seniority bonus. Section 2 of Article 25 refers to the Collective Agreement or the employment contract itself for the specific regulation of this bonus (amount, calculation, etc.).
Article 25.1 ET : 1. The worker, depending on the work performed, may be entitled to an economic promotion under the terms established in the collective agreement or individual contract.
The amount is usually set in three-, four- or five-year periods and the base salary is taken in a certain percentage for its calculation.
As for temporary fixed-term workers, the periods in which there has been no effective provision of services are also taken into account when calculating their seniority. This was decided by the Supreme Court in a unification of doctrine on September 20, 2016 , as we explained in the post “ the seniority of temporary fixed-term workers ”, the contractual link with the company has been in force since its beginning, regardless of the distribution of the times of provision of services in response to calls.