Aim: The review aimed to identify and explore the association of level of support received by people with severe mental illness in supported accommodation and participation. Method: The authors conducted a systematic search in MEDLINE, PsychINFO, PsychARTICLES, CINAHL Plus and ASSIA. Searches were restricted to articles published in English and participants aged 18 years and over with severe mental illness. Articles were included based on level of support received in mental health supported accommodation, classified according to the Simple Taxonomy for Supported Accommodation, and three factors of participation: social participation, daily living functioning and personal empowerment. Studies of in-patient settings and nursing homes were excluded. The review protocol is registered on PROSPERO (registration number: CRD42019161808). Results: Six articles were included in the review from USA, Australia, Sweden and Taiwan. Factors of participation for people living in accommodation with moderate support and accommodation with high support were explored. Data indicated an association between level of support and participation showing that people living in accommodation with moderate support had increased participation compared to people living in accommodation with high support. Conclusion: This review identified an association between level of formal support and participation. People with SMI living in accommodation with medium support participated in more community occupations, more activities and had a higher level of personal empowerment than people living in accommodation with high support.