Bringing goods back into Australia for which you have already received a TRS refund
If you are aged 18 years or over, you can bring up to AUD 900 worth of goods into Australia duty-free, or AUD 450 if you are younger than 18. Families travelling together can pool this allowance (a couple with one child can bring in a total of AUD 900 + AUD 900 + AUD 450 = AUD 2250 worth of goods into Australia without paying duty or GST). This is called your passenger concession.
If the total value of the goods you are bringing into Australia is greater than your passenger concession, including goods for which you have previously claimed a tax refund under TRS and any purchased overseas:
you must declare all of these goods
you will need to repay the GST refund back on the goods you claimed under the TRS
duty and GST will apply to all items purchased, not just goods over the limit of your passenger concession.
Penalties can apply if you don’t declare that you have goods in excess of your passenger concession.