Background <p>Adverse childhood experiences (ACE) are a widespread public health problem with long-term effects. These experiences may threaten individuals’ hopes for the future and their wellbeing. Although there are studies focusing on the effects of ACE on skills of emotion regulation in the literature, there is limited research on the role of self-efficacy in this field.</p> Objective <p>This study aims to determine the effects of mediating roles of regulatory emotional self-efficacy and future anxiety in the effects of adverse childhood experiences on subjective happiness and the serial mediation effects of these variables.</p> Methods <p>This study was conducted in Turkiye using a cross-sectional design and with a sample size of 518 individuals (51% female, 49% male) who are in the age range of 18–36 and have different socio-economical demographics. The rate of reporting one or more ACEs in the sample was 68.4%. This study used a serial mediation model, which included regulatory emotional self-efficacy as first-order mediator and future anxiety as second-order mediator.</p> Result <p>The results showed that both regulatory emotional self-efficacy and future anxiety played a mediator role in the relationship between adverse childhood experiences and subjective happiness. Additionally, with serial mediation effects, adverse childhood experiences reduced future anxiety and contributed to subjective happiness through regulatory emotional self-efficacy. This study demonstrated the importance of regulatory emotional self-efficacy development in practices geared towards increasing subjective happiness in adults with adverse childhood experiences.</p>