BACKGROUND: Patient participation is key in person-centred care, emphasizing individual choices in treatment. Oral health, integral to overall well-being, is sometimes a neglected part of health. This intervention introduces a novel approach to strengthen person-centred care in homecare settings, employing collaborative, interprofessional teamwork and shared documentation across care organizations. This protocol outlines the design of a cluster-randomized controlled trial (RCT) in Sweden, comparing traditional oral assessments with an interorganizational, team-based oral health care planning model facilitated by a shared digital platform for documentation. The overall aim is to evaluate a person-centred interprofessional and interorganizational model for oral health care planning supported by a digital platform to enable healthy ageing. METHODS/DESIGN: The intervention, co-designed with older adults, academic institutions, healthcare providers in public dental care, and municipal organizations, will undergo ethical approval. The RCT will randomize older adults, dental hygienists (DHs) and nursing assistants (NAs) into two groups. The intervention group will attend a two-day workshop on a person-centred, three-step team-based model, while the control group will continue using standard procedures. Thereafter, the three-step collaborative model will be compared to standard procedures. Primary outcomes will be measured using the Revised Oral Assessment Guide (ROAG) and the General Oral Health Assessment Index (GOHAI). Secondary outcomes include health economic evaluations, participation rates and quality of care assessments. Qualitative studies from theoretical perspectives of change and learning based on interviews with key stakeholders will be conducted in both the test and control groups. DISCUSSION: Taking a co-produced approach where theory and practice shape the research iteratively, a person-centred health care planning model supported by a shared digital platform for home settings is evaluated. Anticipated outcomes include improved oral assessments and a deeper understanding of effective person-centred care practices. The co-produced approach of the intervention is also expected to further develop knowledge regarding co-production within domains of healthy ageing from an oral health perspective. As such, the intervention shapes and fosters co-produced person-centred care and healthy ageing. TRIAL REGISTRATION: ClinicalTrials.gov NCT06310798. Registered on 13 March 2024.