Scientific knowledge on the impact of a gender-affirming transition on intimate partners of transgender and gender diverse (TGD) individuals is limited. It is unclear which care needs partners have and which role health care professionals can play during this transition process. The aim of this study was to explore the unique experiences and care needs of people partnering with TGD people in the context of a gender-affirming transition. A qualitative research method was chosen, and a semi-structured interview was conducted with a sample of nine participants. After transcription, thematic analysis was used to analyse the data. Three main themes, with three subthemes each, were identified: (1) intrapersonal processes, with (1a) the process of acceptance, (1b) concerns surrounding the medical transition and (1c) impact on sexual orientation as subthemes; (2) dyadic processes, with (2a) the importance of mutual commitment, (2b) experiences regarding intimacy and (2c) relational growth as subthemes; and (3) perception of support, with (3a) need for support, (3b) the importance of support and (3c) evaluation of support as subthemes. The results suggest that health care providers can help partners to navigate the process of a gender-affirming transition; however, the care needs of partners are currently not satisfied with the available professional support.