Psychotic symptoms can be highly debilitating for those experiencing them. Community members, including family and friends, can play a crucial role in providing support to a person during the early stages of psychosis, provided they have the necessary resources. Mental health first aid guidelines for psychosis have been developed for high-income countries and this study aimed to adapt those guidelines for Brazil. A Delphi expert consensus method was used to gather the views and opinions of 28 health professionals and 24 individuals with lived experience of psychosis in Brazil over two survey rounds. Firstly, 403 statements were translated from English to Brazilian-Portuguese. In the Round 1 survey, participants were asked to rate each statement based on how important they believed it was for it to be included in the Brazilian guidelines. They were also asked to suggest new actions if they wished. Consensus was reached on 257 statements. Eight new statements were created and endorsed from panelists’ comments, and a further 45 statements were unique to the Brazilian guidelines. There was a modest level of similarity between the English-language and Brazilian guidelines. However, the Brazilian guidelines had a greater focus on the importance of family support for people with psychosis and stigma as a possible barrier for openly discussing help-seeking actions for mental health problems in Brazil.