The interface between Australia's aged care and disability systems has come into sharper focus with the 2023 Review of the National Disability Insurance Scheme (NDIS) recommendation to retain the upper age limit for entry and the introduction of an age criterion for assessment in the Aged Care Act 2024. Both are set at age 65. This precise administrative boundary contrasts with the considerable movement across the two systems in practice and prompts examination of these flows from the perspective of the populations in the ‘interface’ age groups, 60–64 and 65–69 years. 

This paper reviews the development of eligibility criteria that have created overlap between the aged care and disability systems, describes the scale and characteristics of the interface populations and analyses the patterns of service use across the age 65 boundary. 

The findings lead to the conclusion that sharpening the age division will not resolve the boundary between the disability and aged care systems. Instead, further analysis from a policy and program perspective is proposed to understand how the issues have arisen and how they might be addressed.