In some Scandinavian countries, the United Kingdom and the United States, there is evidence of a dramatic decline in adolescent emotional wellbeing, particularly among girls. It is not clear to what extent this decline can be generalised to other high-income countries. This study examines trends over time (2005-2009-2013-2017) in adolescent wellbeing in the Netherlands, a country where young people have consistently reported one of the highest levels of wellbeing across Europe. It also assesses parallel changes over time in perceived schoolwork pressure, parent-adolescent communication, and bullying victimization. Data were derived from four waves of the nationally representative, cross-sectional Dutch Health Behaviour in School-aged Children study (N = 21,901; 49% girls; Mage = 13.78, SD = 1.25). Trends in emotional wellbeing (i.e., emotional symptoms, psychosomatic complaints, life satisfaction) were assessed by means of multiple regression analyses with survey year as a predictor, controlling for background variables. Emotional wellbeing slightly declined among adolescent boys and girls between 2009 and 2013. A substantial increase in perceived schoolwork pressure was associated with this decline in emotional wellbeing. Improved parent-adolescent communication and a decline in bullying victimization may explain why emotional wellbeing remained stable between 2013 and 2017, in spite of a further increase in schoolwork pressure. Associations between emotional wellbeing on the one hand and perceived schoolwork pressure, parent-adolescent communication, and bullying victimization on the other were stronger for girls than for boys. Overall, although increasing schoolwork pressure may be one of the drivers of declining emotional wellbeing in adolescents, in the Netherlands this negative trend was buffered by increasing support by parents and peers. Cross-national research into this topic is warranted to examine the extent to which these findings can be generalised to other high-income countries.