Background: A high sense of subjective well-being has been associated with more prosocial behaviours, better health, work productivity and positive relationships. The aim of this systematic review was to explore what impact self-advocacy has on the subjective well-being of people with intellectual disabilities. Method: The authors reviewed articles focusing on the perspectives of adults with intellectual disabilities engaged with self-advocacy groups. Searches were performed in PsychINFO, Web of Science, SCOPUS, MEDLINE and CIHNL databases, resulting in 16 articles meeting the inclusion criteria. A framework synthesis approach was used to extract data deductively based on the Dynamic Model of Wellbeing. Results: While self-advocacy has a positive impact on all domains of the Dynamic Model of Wellbeing, negative impacts associated with participation in a self-advocacy group were also reported. Conclusions: The benefits of participating in self-advocacy groups on the well-being of individuals with intellectual disabilities outweigh the disadvantages.