The debate on age-segregated housing for older prisoners has seldom captured the perspectives of older prisoners and professionals (‘stakeholders’) working in a European prison setting. To address this gap in the research, 35 older prisoners from Switzerland and 40 stakeholders from three European countries (including Switzerland) were interviewed for the study. Data analysis was conducted thematically, and the validity of coding was established independently from the primary author. Interpretation of study results was agreed upon by all authors. Participants' opinions regarding age-segregated housing for older prisoners were split. An almost equal number of prisoners and stakeholders had similar arguments in favour of and against such living arrangements. The findings encompassed three major themes: ‘prisons should mirror society’ and thus age-mixed housing was preferable as it ensured generational exchange; a ‘separate unit within the prison’ would allow continuity of personal and other relationships and at the same time respond to older prisoners' specific health and environmental needs; finally, participants felt it was important to think critically about ‘the criteria’ for placing older prisoners in an age-segregated arrangement. We conclude that the debate on consolidated versus separate housing is bifurcated. Any push towards segregation based only on high prison violence and unvalidated context-specific information may result in unreliable public policy.