Improving higher education access, experience and outcomes for students with disabilities (SWD) is an explicit performance target and goal for Australian universities. Prevalence of SWD vary greatly by institution and are considered under-reported. International research identifies SWD failure to disclose to institutions as a major concern for providing appropriate support to success for this equity group. The number of “hidden” or “invisible” disabilities that impact on learning is well known, but the actual numbers of students who deal with these in Australian universities is unknown. This project aims to identify SWD who do not disclose and to explore the reasons behind their non-disclosure.A cross-sectional survey was offered to the students of an Australian regional university in order to identify the size of the non-disclosed population dealing with learning difficulties, ongoing medical conditions, mental health issues and physical challenges that impact on learning. Using a modified version of the UK Higher Education Statistics Agency (HESA) disability categories, students identified diagnoses/assessments and their institutional disclosure status. The diagnoses/assessments identified were called “learning challenges” in order to focus students on the results of the various disabilities in terms of their learning. The survey collected demographics, enrollment detail and existence of assessments/diagnoses of learning challenges with detail on institutional disclosure and reasons behind non-disclosure. Reasons for non-disclosure were further explored with open-ended questions around learning impacts and suggestions for improving experience of learning at university. Statistical analyses of the valid responses received for the domestic undergraduates (n=2821; 13.2% of DOM UG population) were completed in terms of size of the population with learning challenges, what reasons are given for choosing non-disclosure and the use and importance of various formal and informal supports. The non-disclosing sub-sample of students with learning challenges (n=633, 24.4% of the sample) is more likely to be younger (under 25) with an HSC entry pathway than the disclosed sub-sample. Students with two or more learning challenges are more likely to disclose to the institution than those with only one learning challenge. In terms of the learning challenges themselves, students dealing with ongoing medical conditions and physical disabilities are more likely to disclose whereas students with mental health issues are less likely to disclose. Non-disclosing students are also less likely to use any of the institutional supports than disclosing students. Implications for institutions in terms of academic support are explored through the suggestions of the non-disclosing students.