Context: Calls to collect patients’ race/ethnicity (RE) data as a measure to promote equitable health care among vulnerable patient groups are increasing. The COVID-19 pandemic has highlighted how a public health crisis disproportionately affects racialized patient groups. However, less is known about the uptake of RE data collection in the context of mental health care services. Methodology: A qualitative case study used surveys with mental health patients (n = 47) and providers (n = 12), a retrospective chart review, and a focus group to explore healthcare providers’ and patients’ perspectives on collecting RE data in Canada. Results: The patient survey data and focus groups show that patients avoid providing identifying information due to perceived stigma and discrimination and a lack of trust. Providers did not feel comfortable asking patients about RE, leading to chart review data where RE information was not systematically collected. Conclusions: The uptake and implementation of RE data collection in mental health care contexts require increased training and support, systematic implementation, and further evaluation and measurement of how the collection of RE data will be used to mitigate systemic racism and improve mental health outcomes.