Access to mental healthcare (MHC) is one of the social determinants of mental health that underlies the large mental health disparities faced by trans and non-binary people (TNB). TNB people may seek MHC for reasons related specifically to gender-affirming needs or for general mental health needs, which also needs to be affirmative of their gender. The topic of general MHC access has received some research, but there are still gaps regarding examining specific MHC settings and demographic differences. Furthermore, research in Aotearoa/New Zealand is still scarce being composed mainly of the Counting Ourselves survey. This thesis aimed to describe the rates of different MHC access indicators for TNB people in Aotearoa/New Zealand, including utilisation, unmet needs, satisfaction levels, and barriers to access. Subsequently, to examine demographic differences in these indicators across age, gender/sex assigned at birth (SAAB), and ethnicity groups. Demographic differences were hypothesised based on existing inequities. Analyses of data from the Counting Ourselves 2022 study were performed, which employed a cross-sectional methodology. Measures included demographic data, use of different MHC providers, unmet need for MHC, satisfaction with different MHC providers, and general and trans-specific barriers to MHC. In total, 2,631 valid responses were analysed, with almost all participants (99.8%) completing the survey online. All participants lived in Aotearoa/New Zealand, and their ages ranged from 14 to 86, with an average age of 27.1. The most common gender/SAAB groups were non-binary AFAB (43.7%) and transgender women (22.1%), while the most frequent ethnicity groups were European (75.3%) and Māori (13.9%). Results showed that the majority (58.1%) of participants had accessed at least one MHC service in the past year, with private MHC professionals being the most frequently accessed provider. Younger participants and non-binary AFAB were more likely to use MHC services, while service use did not differ significantly by ethnicity. Most participants (59.6%) reported an unmet need for MHC in the past year, with younger participants and non-binary AFAB participants being more likely to report this. Satisfaction with MHC providers was relatively positive, but approximately one-third of participants expressed dissatisfaction. Older participants were more satisfied with MHC, and transgender women were more satisfied, only in comparison with transgender men. The most frequent barriers to accessing MHC that are shared with the general population were cost (57.4%) and lack of knowledge of services (44.8%). The most frequent trans-specific barriers were fear of professionals lacking understanding of TNB people (50.2%) and fear of pathologisation (48.9%). Participants reporting most trans-specific barriers were more likely to be younger, and non-binary AFAB participants were more likely to report fear of insufficient understanding and fear of misgendering from providers. These findings indicate that younger and AFAB TNB people may face additional barriers to accessing and being satisfied with MHC, suggesting a need for targeted interventions. Overall, ethnicity did not significantly predict MHC access indicators, suggesting that it might not be a strong predictor of these within this population. Nevertheless, ethnicity findings differ from patterns observed in the general population of Aotearoa/New Zealand, calling for more targeted research. The high rates of use of MHC services as well as unmet needs and experienced barriers underscore the importance of addressing barriers and improving MHC accessibility and quality for TNB people. This should include improving MHC providers’ education and training, as well as implementing routine procedures to ensure a culturally safe and respectful environment.