Background: Hospice-at-home aims to enable patients approaching end-of-life to die at home and support their carers. A wide range of different service models exists but synthesised evidence on how best to support family carers to provide sustainable end-of-life care at home is limited. Aim: To explore what works best to promote family carers’ experiences of hospice-at-home. Design: Realist evaluation with mixed methods. This paper focuses on qualitative interviews with carers (to gain their perspective and as proxy for patients) and service providers from 12 case study sites in England. Interviews were coded and programme theories were refined by the research team including two public members. Setting/participants: Interviews with carers (involved daily) of patients admitted to hospice-at-home services (n = 58) and hospice-at-home staff (n = 78). Results: Post bereavement, 76.4% of carers thought that they had received as much help and support as they needed and most carers (75.8%) rated the help and support as excellent or outstanding. Of six final programme theories capturing key factors relevant to providing optimum services, those directly relevant to carer experiences were: integration and co-ordination of services; knowledge, skills and ethos of hospice staff; volunteer roles; support directed at the patient–carer dyad. Conclusions: Carers in hospice-at-home services identified care to be of a higher quality than generic community services. Hospice staff were perceived as having ‘time to care’, communicated well and were comfortable with dying and death. Hands-on care was particularly valued in the period close to death.