We are required to send details of your private health insurance to the ATO. If you do your tax online, select the pre-fill option and the details should populate. If you use a tax agent, they should also be able to access the information.
If you choose to lodge a paper tax return, you'll need a copy of your Private Health Insurance Statement which can be downloaded from the self-service portal.
For help on what sections you’ll need your statement for, visit the ATO website.