Across the subjects of economics, sociology and demography, much has been written about the difficulties faced by immigrants. However, much less attention has been paid to the difficulties which return migrants face when they come back to live in their countries of birth. A number of studies suggest that return migrants can experience significant re-adjustment challenges. In this paper, we add to this strand of research by examining the extent to which a group of returned migrants experience higher degrees of social isolation and loneliness compared to compatriots who never lived outside their country of birth. The data used are from the first wave of the Irish Longitudinal Study on Ageing (TILDA). Our results suggest that social isolation is a significant feature of the lives of return migrants and that the degree of social isolation is typically stronger for people who spent longer away and who have returned more recently