13th salary: what is its nature, who is entitled to it and how is the annual bonus calculated? The employer is not obligated to pay the 13th salary: there is no such concept in the labor law, and it may not be found in the company's internal documents. But if the procedure and terms of the annual bonus are set in the employment contract, the collective agreement or the local law, and the employee complied with them, the money must be accumulated. Who is entitled to the 13th salary, how is the annual bonus calculated and how much will I get after deducting personal income tax - in the MK material. Photo: Lilia Charlovskia.