There are situations when employers send employees to trainings improving their professional qualifications outside their working hours or on non-working days, e.g. on Saturday or Sunday. According to Art. 100 of the Labor Code, the employee is obliged to follow the instructions of his superiors related to the work. Undoubtedly, this also applies to the instructions that concern compulsory participation in training, even if it is organized on a day off from work. The Labor Code does not contain any regulations regarding the inclusion of training courses aimed at increasing the employee’s professional qualifications in the working time. Only in the case of occupational health and safety training, the legislator clearly indicated that they take place during work and at the expense of the employer. It is legitimate to believe that employee training on a day off is included in his working time only if participation in it is mandatory for the employee. Most of the doctrine expresses the view that counting the time spent on training to working time should depend on:

• instructions to the employee to participate in training courses organized by the employer,
• the nature of such training.

Any training of the employee on the day off, in which the employee’s participation resulted from the official order issued by the supervisor, should be considered as working time. In addition, if training to raise qualifications: is of a specific nature, is closely related to work and the acquisition of skills required only for work for a given employer, they are included in the working time. If, on the other hand, the employee’s training on a day off is voluntary, and participation in it, although organized or indicated by the employer, does not belong to the basic obligations of the employee defined in Art. 100 of the Labor Code, the employee will not be entitled to compensation for the training time. If the compulsory training takes place on a non-working day, this time may be considered overtime because the average weekly working time is exceeded. The employer is obliged to grant the employee a whole day off, even if the training on the day off was shorter than the daily working time of the employee. A day off is granted in a given settlement period on a date agreed with the employee. For a day off granted in return for participation in training taking place on a day off, the employee must be paid the normal wage. The employee should be granted time off, and if this is not possible, then appropriate remuneration together with a possible supplement for overtime work. It should be borne in mind that training time is the time of actual training, i.e. the time of training classes.

Source: https://poradnikprzedsiebiorcy.pl/-szkolenie-pracownika-w-dniu-wolnym-jaka-rekompensata-w-zamian