This cross-sectional study assessed international rehabilitation practitioners’ views of mental health assessment (MHA), related specifically to assessment tools and needs in the field. We delivered an anonymous web-based survey capturing rehabilitation practioners’ perspectives on MHA practices, assessment tools, and needs through the American Congress of Rehabilitation Medicine in the USA and through national rehabilitation networks in Finland and Norway. Altogether, 355 rehabilitation professionals answered the survey. Unmet MHA needs, most often attributed to insufficient time (112/269 responders), were recognized among rehabilitation professionals irrespective of the country of practice. When professional experience was weighed against barriers to conducting MHA, cost was statistically significantly linked to professional experience, with those with less experience viewing cost more as a barrier (P=0.019). Rehabilitation professionals from different professions, in different countries, and working with a variety of clinical populations recognize defined barriers to MHA in rehabilitation.