BACKGROUND The effective size of the optometric workforce is dependent on graduate numbers, retention rates and immigration and is influenced by age, gender and working hours of optometrists. This paper presents modelling results of the relationship between the projected Australian optometric workforce and projected demand for optometric services for the period 2011 to 2036. Nine hypothetical optometric supply-side and demand-side scenarios are presented. METHODS Data from the Australian Bureau of Statistics on age and gender of people listing optometry as their major qualification in the 2011 census were projected over a 25-year period, accounting for factors such as concordance with Health Workforce Australia figures for registered optometrists in Australia in 2011, ageing, attrition, hours worked, new graduates and immigration. Data were compared to the numbers of optometrists calculated as necessary to meet the demand for services of the Australian population to 2036 using nine different scenarios. RESULTS It was estimated that there would be a surplus of over 1,200 equivalent full-time optometrists (EFTO) in 2036 for the highest service demand scenario of 13.8 million Medicare services, where 21 hours of a 38-hour week per EFTO were allowed for the provision of optometric services under Medicare. Substantial surpluses were predicted in all states and territories except Queensland, Tasmania and the Northern Territory where predicted supply was within six EFTO of predicted demand. CONCLUSIONS Projections using current weightings for mortality, attrition, proportion of optometrists in active practice, working hours, immigration, new graduates and 21 hours per EFTO per week available for Medicare services indicate that in 2036, there will be excess optometrists in relation to projected demand for services, if service utilisation is maintained at current levels or increased by 10 or 20 per cent. Substantially greater excesses result if each EFTO has 28 or 35 hours per week available for Medicare services.