Objective The aims of this study were to compare and contrast the information three Australian private health insurance funds (HCF, Bupa and Medibank) have provided on their online out-of-pocket cost tools and to consider the implications this has for price transparency in Australia. Methods Website data were downloaded from HCF, Bupa and Medibank on 18 February 2019. The information and statistics provided on these pages were reviewed, and the procedures compared across funds if their pages had referred to the same Medicare Benefits Schedule (MBS) item(s). Information was extracted regarding descriptions of the claims data used, the types of statistics provided, the out-of-pocket estimates, the total procedure cost, the MBS items referenced and the assumptions the funds described on their pages. Results HCF specified the MBS items used to select the claims data for their estimates, whereas Bupa and Medibank only referred to common MBS items associated with the procedures. On average, HCF had 1.44 more MBS items listed than Bupa and 2.08 more than Medibank. The funds organised procedures differently, such as HCF providing separate cost estimates for vaginal, abdominal and keyhole hysterectomy compared with Medibank's single estimate for hysterectomy costs. Conclusions These funds have started to address the need for transparent out-of-pocket cost information, but the differences across these pages demonstrate complexities and the potential obfuscation of cost data. What is known about the topic? Out-of-pocket costs are highly variable and patient 'bill shock' is an increasing concern in Australia. Private insurance funds have created online tools to share procedure cost estimates based on their claims data. What does this paper add? This is the first review of Australian insurance funds' price transparency tools. The cost information is difficult to interpret both within funds (for members) and across funds (for the system). What are the implications for practitioners? Policy makers will need to consider the complexities and presentation options for cost estimates within the health system if they move ahead with a public price transparency tool. There is still a requirement for cost information that can facilitate price shopping across providers and funders.