How long is a confirmation of guaranteed work or an employment permit valid?

Confirmations of guaranteed work are issued with a maximum validity of 26 weeks. If a confirmation of guaranteed work was issued for a shorter period, it can be extended for a total of up to 26 weeks. In justified cases, it may be extended for up to 36 weeks. Employment permits are also issued for a fixed term only. The maximum validity of an employment permit is one year. If it is foreseeable that employment, by its very nature, will end before a given period of time (e.g. theatre summer season), the employment permit may be issued only for the required period (on extension see Can an employment permit be extended?).

If the employment is terminated prematurely, the employment permit becomes invalid upon termination.