Background The international development of health care, an ageing population and rapid technical development mean that more care is being performed in patient homes. This care environment is often unpredictable and involves both formal and informal caregivers, making it potentially unsafe. There is sparse knowledge about how patient safety is protected in home health care in Sweden and how registered nurses work to prevent risks and promote safe care. Aim The aim of the study was to explore registered nurses' efforts to reduce perceived risks for home-dwelling older patients and ensure safe home health care. Method We used a qualitative design with individual interviews with 13 registered nurses working in municipalities in southeast Sweden. The narratives were analysed with inductive content analysis. Findings The findings showed that the registered nurses tried to secure a safe care environment and took an active role in care, striving to stay one step ahead of the patient. These three types of efforts are likely interdependent, suggesting they are all needed to reduce perceived risks for home-dwelling older patients and ensure patient safety in home health care. Conclusions It is a challenge for registered nurses to maintain patient safety when performing care in patient homes. Continuity of care is required and must be based not only on self-reliance among registered nurses but also on trusting relationships with patients, next of kin, colleagues and other personnel, as well as on the development of organisational conditions adapted to patient needs.