Patient and public involvement (PPI) is increasingly embedded in stroke and aphasia participatory research, enhancing relevance and inclusivity. While the benefits of PPI are well-documented, the costs, both direct (eg, honoraria, travel, accessibility materials) and indirect (eg, time, administrative burden, emotional labour), remain poorly reported. This scoping review aims to (1) identify and categorise direct and indirect costs of PPI in stroke research, (2) examine how these costs are defined, reported or implied, (3) map cost-related barriers and facilitators and (4) expose evidence gaps to inform the Mapping the Economic and Social Tangible and Emotional Resources of Patient and Public Involvement (MASTER-PPI) framework.

Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines, we will search Medline, PUBMED, Embase, CINAHL, APA PsycINFO, Scopus and Web of Science, as well as grey literature (NIHR INVOLVE, Horizon Europe, non-governmental organisation (NGO) reports). Eligible studies include those reporting or implying direct or indirect costs of PPI in stroke research. Two reviewers will independently screen and extract data, which will be synthesised descriptively and thematically. Findings will be aligned with the MASTER-PPI framework.

Ethical approval is not required. The findings will be disseminated through peer-reviewed journal publications, conference presentations, social media posts in lay language and policy briefs tailored for NGOs and funders.

This protocol is registered with the Open Science Framework (OSF) (https://doi.org/10.17605/OSF.IO/VM9ZU).