INTRODUCTION: Transgender and gender diverse individuals experience a variety of barriers to accessing culturally responsive care across different types of health services. This study develops and validates a scale to assess for trans-inclusive healthcare practices, which may be used in a variety of ways. METHODS: The authors and community partners developed 34 initial practices indicating provider inclusivity of transgender and gender diverse patients. Data were collected in 2018, using an online survey of transgender and gender diverse adults in Michigan (n=626), analyzed in 2019. RESULTS: An exploratory factor analysis was conducted. The following 6 components were retained with 27 items: trans-inclusive messaging, name/pronoun usage, outreach, gender-affirming practice, referral comfort, and inclusive intake forms. Full sample analysis showed Cronbach's α to be 0.91. The sample was split in half to run 2 sets of cases in a principal components analysis, Sample A (n=323) and Sample B (n=303). Percentage of variance explained and Cronbach's α were consistent across samples, giving evidence to reliability and validity. CONCLUSIONS: Findings suggest that the Trans-Inclusive Provider Scale may be useful in identifying providers' behaviors regarding inclusivity of transgender and gender diverse patients and provide growth opportunities at both individual and practice levels. It could also guide improvements after trainings or be used as a micro-intervention, allowing providers to assess behaviors and identify opportunities to improve.