Top 10 private health insurance companies in Australia by market share Medibank: 26.9% market share. Bupa: 25.4% market share. HCF: 11.7% market share. nib: 9.2% market share. HBF:7.3% market share. Australian Unity: 2.6% market share. Teachers Health: 2.5% market share. GMHBA: 2.1% market share. More items... Jan 24, 2022