Abstract Background The ADVANCE project aims to address mental health disparities among people in a situation of vulnerability in Europe. Through a co-creation approach, workshops were conducted to devise stigma prevention strategies during the implementation of mental health promotion interventions for migrant populations in Italy and Denmark. Methods The methodology involved two rounds of scenario-based workshops, a participatory method that elicit expert opinions to solve local problems and anticipate future ones. Round 1 included two separate workshops with (1) end-users and umbrella organizations, and (2) healthcare practitioners and decision-makers, to ensure diverse perspectives and minimize the impact of power imbalances. Participants brainstormed strategies to minimize stigma and optimize the intervention scenario. In Round 2, a mixed-group workshop was held to refine the strategies. Workshops occurred in Copenhagen and Verona in March 2024. Content analysis of the data was carried out. Results In Denmark, discussions emphasized tailored presentation of the intervention promoting shared experiences and normalizing mental health challenges, language sensitivity, participation through self-identification, and attention to relational aspects in intervention delivery to combat stigma effectively and enhance acceptability and engagement with the intervention. In Italy, proposed strategies included group exercises to raise awareness and promote open dialogue about cultural differences, language barriers, and discrimination. Discussions also considered the intersectionality of stigma, including factors like gender, socioeconomic status, and sexual orientation. Common themes included language sensitivity, facilitator training, and inclusive and safe spaces. Conclusions Scenario-based workshops can be a valuable tool to facilitate the co-creation of stigma-prevention strategies while involving all stakeholders in promoting effective mental health interventions. Key messages • Co-creation approach fostered stakeholder collaboration, yielding tailored strategies that promote inclusivity, acceptability and engagement with mental health interventions for migrant populations. • Context-specific approaches that emphasize trust, confidentiality and cultural sensitivity were prioritised to tackle stigma when implementing interventions and promoting mental health equity.