BackgroundReciprocal relationships between researchers and patient and public involvement (PPI) contributors can enable successful PPI in research. However, research and anecdotal evidence suggest that researchers do not commonly provide feedback to PPI contributors thus preventing them from knowing whether, how or where their contributions were useful to researchers and research overall.AimsThe aim of this study was to explore the variation, types, importance of, and satisfaction with feedback given by researchers to PPI contributors in six PPI groups in England, and identify the barriers to the process of feedback.MethodsAn explanatory mixed methods sequential study design with a questionnaire survey followed by semi‐structured interviews with researchers and PPI contributors in six PPI groups. PPI contributors were involved in all stages of the research process.ResultsResearchers do not routinely give feedback to PPI contributors. Feedback was found to have different meanings: an acknowledgement, impact and study success and progress. PPI contributors who receive feedback are motivated for further involvement; it supports their learning and development and prompts researchers to reflect on PPI impact. The importance of the role of a PPI lead or coordinator to facilitate the process of providing feedback was also highlighted.ConclusionThis study found no generic way to give feedback indicating that mutual feedback expectations should be discussed at the outset. PPI feedback needs to become integral to the research process with appropriate time and resources allocated. PPI feedback can be seen as a key indicator of mature, embedded PPI in research.