In Brazil, little data is available to inform HIV prevention programming for travestis and transgender ('trans') women, despite the existence of a social movement that has gained strength in recent years. We conducted formative research in Rio de Janeiro to gather trans women's perspectives on combination HIV prevention approaches. Framing the analysis within the model of gender affirmation, we found that several social and contextual factors inhibited participants' access to HIV prevention and treatment. Experienced and anticipated gender-related discrimination and HIV stigma were linked to the avoidance of HIV testing, health services and HIV status disclosure. Participants recommended HIV prevention interventions which combined socio-structural interventions, such as peer-based empowerment and social support, with biomedical interventions such as pre-exposure prophylaxis (PrEP). Participants expressed a preference for programmes and interventions that emphasised a gender-affirmative approach, promoted autonomy and aimed to reduce stigma and discrimination in public health services.