The benefits of caseload midwifery care are clearly documented, and many policy documents in Australia support its expansion. Despite this, little is known about the availability of caseload across Australia, nor about what proportion of women have access to a caseload model. This paper describes caseload midwifery in the public maternity system in Australia; its prevalence, and factors associated with implementation and sustainability.A cross-sectional online survey of maternity managers of public hospitals that provide birthing services throughout Australia.Sixty-three percent (149/235) of eligible participants responded. Respondents were from all states and territories, metropolitan, regional and remote areas, and from hospitals with very small to very large birth numbers. Only 31% reported that their hospital offers caseload midwifery, and an estimated eight percent of women received caseload care at the time of the survey, most of whom were considered to be of 'low obstetric risk'. Many respondents were planning to implement or expand caseload. Key factors associated with the implementation of caseload were funding to establish the model, the interest and availability of staff to work in the model, organisational support and perceived consumer demand.This is the first study to explore caseload implementation at a national level. Although the number of services offering caseload midwifery care has increased nationally, access remains relatively limited. Women who live in metropolitan areas and who are considered at 'low obstetric risk' are most likely to be able to access this model. Funding and support for establishing new models are the main barriers to implementation.