Salary (its amount, structure (salary (tariff rate), bonuses, allowances, surcharges), terms of establishment and payment) is an essential condition of the employment contract.
An increase in official salaries – wages by the employer may not have exclusively positive consequences for the employee, which is caused by both objective reasons (for example, deprivation of the right to certain social benefits (taking into account income for the purpose of housing subsidy, etc.) and subjective factors – perception of salary increase by the employee himself (salary review was carried out unfairly, because other employees were given higher salaries, economic mobbing).
Norms of Art. 9-1, 21, 97 of the Labor Code provide that the decision to change the terms of employment contracts, even if they relate to an increase in wages, must be agreed by the employer with the representatives of the employees, and to introduce new terms of payment, the agreement of both parties to the employment contract must be reached.
Therefore, employees must be warned about salary increases (changes in the amount or structure of wages) before the introduction of new terms of payment.