However, as always, there are exceptions.
If a clause in an employment contract stipulates that employees must be available at all times, even when on holiday, it should be checked whether this rule is permissible, advises the Bund-Verlag. According to a ruling by the Federal Labour Court in 2000, such agreements are not permitted in employment contracts. According to the Bund-Verlag, this applies at least to the minimum of 24 working days to which every employee is entitled.
However, permissible are special contractual rules on all additional days of leave voluntarily granted by the employer. Here employers can demand that workers be available even while on holiday.
Reachable in an emergency
In addition to such special clauses in job contracts, there are some exceptional situations in which a call or message from the employer may be legitimate - for example if the staff member on vacation is the only person who knows a particular password.
By the way, ignoring a call or e-mail from the employer is not grounds for dismissal. Getting fired for behavioural reasons requires a prior warning - and under German labour law, vacationing employees cannot be accused of neglecting their duties.