Where are my details held if I link my australia.gov.au account to an agency online account or I register for an agency online service through australia.gov.au?
All details that you supply to an Australian Government agency online service through australia.gov.au are held by that agency in their own systems. Linking your agency online service to an australia.gov.au account does not cause the information to be held by australia.gov.au.
australia.gov.au does provide the option for you to enter some details for the personalisation of your account. In the future some information, (such as your address) may be used to answer questions asked through australia.gov.au. Your permission to do this will always be sought first.