AIM: To explore communication research in nursing by investigating the theoretical approaches, methods, content and perspectives in research on real-time registered nurse (RN)-patient communication. DESIGN: An integrative review of real-time communication between RNs and patients. DATA SOURCES: Empirical research papers were searched in PubMed, CINAHL Plus and Medline. The results from the database searches were supplemented with results from manual searches in reference lists. REVIEW METHODS: A total of 1369 articles published between January 1996 and December 2021 were screened, which resulted in the inclusion of 52 articles. RESULTS: The integration of various theories, such as nursing or communication theories, is weak in most of the included studies. RN-patient communication appears to influence relationship building. Even when nurses strive to meet patients' needs, they often focus primarily on nursing routines and physical care. The topic of the communication varies depending on the situation and different communication styles are used. When a patient-centred approach is adopted, the interpersonal communication becomes quite symmetrical, with complementary roles of nurses and patients. Within a more asymmetric communication context, nurses dominate communication, choose topics and function as instructors. How the nurses communicated subsequently influenced the patients' communication styles and strategies. CONCLUSION: Communication is multifaceted, contains different strategies and is important for building trust and facilitating patient-centred care. The importance of RNs' communication for interaction and relationship-building seems to be well established within research, but few studies focused on patients' communication with RNs. IMPACT: This integrative review gives an overview of the width and depth of observational studies on RN-patient communication research. The variety of studies indicates that this area is a less well-grounded field of research. Future research is warranted to support nurses in their communication, especially regarding the exploration of patients' communication and desired communication skills in nurse-patient interactions. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution was included in this integrative review.