Health Minister Sussan Ley "expects" private health funds to pass on savings from the cost of medical implants to customers through lower premium increases, but can't say what those savings will be.

Ms Ley announced the $86 million cut to the Prostheses List, which sets down how much funds pay for the devices used in hip replacements, pacemakers and the like, as a "down payment" for future reform.

Over the next six years, costs will be wound back by $500 million, with Ms Ley saying she believed the move would immediately flow down to customers of health funds, through lower premium increases next year.

She could not say by how much fees would be reduced, or if premium holders would be guaranteed their health fund had passed on any savings.