Objectives: The study sought to explore the relationship between social support, engagement and health in online support groups (OSG) for family carers. Using the social identity approach it was anticipated that social identity was a key factor driving any association between social support, engagement and perceived stress. We hypothesised, first that those engaging with OSG would report lower levels of social support in real life compared to those who did not engage with OSG. Second, that those who engaged with OSG would report higher social support from their OSG members, and this would be correlated with a higher social identity with OSG members and together these would be associated with lower perceived stress in OSG members. Design: Data was collected using an online survey. The survey was distributed through representative family caregiver support services nationally and internationally and made generally available online. Participants self-selected by following the link to the survey. Methods: 137 respondents completed the survey, of those 93% (n=127) were female and 69% (n=96) were white. The age range was 19-72 years old. 62% (n=91)of respondents used OSG, and of this group 25% engaged at least once a day. Results: There was no statistical difference between family caregivers who were or weren’t in OSG from each other in terms of social support in real life, t(134)= -1.25, p> 0.05 and perceived stress (134) = 0.16, p>0.05. Within our OSG group, social identity was a positive predictor of social support, r = 0.64, p< 0.001, Unexpectedly, neither social identity nor social support were associated with perceived stress in this sample. Further analysis will be conducted to explore these results. Conclusions: The findings from this study will contribute to a list of recommendations being developed for use by practitioners, funders and policy makers.