Objective: We studied if preferences about end-of-life care of people having an advance directive (AD) stay stable over time and if (in) stability is associated with health status. Methods: A longitudinal cohort study with a population owning different types of ADs (n = 4638). Respondents repeatedly answered questionnaires between 2005−2010. Using hypothetical scenarios about advanced cancer and dementia we assessed preferences for continuing or forgoing resuscitation, mechanical ventilation, artificial nutrition and antibiotics. Using generalized estimated equations we analysed whether life-events and quality of life influenced changes in preferences. Results: The proportion of respondents with stable preferences ranged from 67 to 98 %. Preferences were most stable concerning resuscitation and least stable concerning mechanical ventilation. In only a few instances we found life-events or a change in quality of life could both increase or decrease odds to change preferences. Conclusion: Preferences concerning continuing or forgoing treatment at the end of life are stable for a majority of people with ADs, which supports their validity. Practice implications: The value of on-going communication about preferences between patients and caregivers is confirmed by our findings concerning differences in stability between treatments and the association between stability of preferences and life-events or quality of life.