The Medicare Levy Surcharge (MLS) is levied on payers of Australian tax who do not have private hospital cover and who earn above a certain income. The surcharge aims to encourage individuals to take out private hospital cover, and where possible, to use the private system to reduce the demand on the public Medicare system.
The surcharge covers you and your dependents. Your dependents include your spouse, any of your children who are under 21 years of age, or any of your student children who are under 25 years of age. For more information about who is considered a dependant for MLS purposes, you can refer to the ATO's Medicare Levy Surcharge page. For more information: Medicare Levy Surcharge