BackgroundDisclosure of human immunodeficiency virus (HIV)‐positive status in a workplace can be a complex social decision for a person living with HIV.ObjectiveTo design a Decision Guide to support people living with HIV in assessing contexts, risks and benefits of workplace disclosure in choosing whether or not, or to what extent, to disclose. In this report, we review the participatory design of a Decision Guide prototype and focus on its evaluation.MethodsWe began with stakeholder input through an environmental scan and community consultation that informed the development of an online Decision Guide prototype. To evaluate the comprehensiveness, acceptability and usability of the prototype, we used qualitative methodology involving individual interviews and the think‐aloud technique. Interviews were transcribed and analysed qualitatively.ResultsFourteen people, including people living with HIV and service providers, participated. We identified benefits of the Decision Guide related to comprehensiveness, acceptability and usability. Additional interview themes focused on disclosure concerns, mitigating risks associated with disclosure and additional considerations for the Decision Guide.ConclusionsThe Decision Guide was perceived to be acceptable, comprehensive and useful. The findings endorse the application of a socio‐ecological perspective when designing decision support aids for complex social decisions.Patient or public contributionPeople with lived experience of HIV were involved in the prototype design phases as research team members. They, along with community leaders and service providers, also participated in a community forum and were key informants for the evaluation of the Workplace Disclosure Decision Guide prototype.