Objectives: Examine differences in mental health treatment-related stigma in student service members and veterans (SSM/Vs) and peers from 57 post-secondary institutions across the United States. Methods: In total, 909 SSM/Vs and 1818 demographically- and institutionally-matched non-SSM/Vs completed assessments of stigma-related barriers to mental health service utilization as part of the Healthy Minds Study between 2011 and 2015. Results: When compared to non-SSM/V peers, SSM/Vs reported more mental health treatment-related stigma toward help-seekers and less confidence in the helpfulness of therapy/counseling and psychotropic medications. However, effect sizes were small in magnitude (ds = 0.10 to 0.16), and depressed students in both groups reported greater stigma. Conclusions: SSM/Vs experience greater treatment-related stigma than non-SSM/V peers, which may deter service use in many cases. However, differences in stigma were small and other under-studied barriers to help-seeking may apply to the substantive subset of SSM/Vs and non-SSM/Vs who may benefit from utilizing available services.