<p>While there is a large literature that examines the determinants of carer quality of life, there is a dearth of research that focuses on the usual activities that carers perform and how they are related to carer-specific measures of quality of life. We use data from the Survey of Adult Carers in England to investigate the role that the tasks that carers perform play in determining carer quality of life. We model the relationship between the variables through a series of simple linear regressions, multiple linear regressions, and a Shapley decomposition. We find that all of the individual tasks that we have information on are statistically significant predictors of carer quality of life. In addition, the Shapley decomposition shows that, when taken together, carer tasks explain a higher proportion of variance in carer quality of life than any other group of determinants. These results are largely robust to different measures of carer tasks, different measures of carer quality of life, and different subgroups. We also find that there is evidence of a causal link between carer tasks and carer quality of life as carers report that their caring responsibilities have affected tangible health outcomes such as illnesses and GP visits. From a policy perspective, local government services that are used to support carers should know that policies designed to help carers with their tasks could have a large impact on carer quality of life.</p>