An Australian tax return can be amended after it has been assessed, generally within two years of the date on the notice of assessment. Amendments run both ways: you can add a deduction you missed, or income you left out. The ATO works to the same two year clock.
What is an amendment for?
An amendment is the ordinary way a lodged return gets put right, and it costs nothing to lodge. It is not a dispute, and most working holiday maker amendments simply produce a larger refund.
- A deduction that was never claimed
- Income from an employer that was left out
- An offset or exemption that was missed
- Figures entered incorrectly
- A Medicare position taken before the paperwork arrived
The last is the most common single reason we amend a working holiday return. A Medicare Entitlement Statement from Services Australia commonly takes weeks to issue, and a return lodged in the meantime went without it.
How long do you have?
Two years from the date of the original notice of assessment, for individuals and small businesses. Four years applies to some other taxpayers, and there is no limit in cases of fraud or evasion.
The clock runs from the assessment, not from the end of the financial year, so a return assessed in September 2026 can be amended until September 2028.
What is the difference between amending and objecting?
Confusing them wastes a deadline. An amendment fixes something that was wrong in the return you lodged. An objection challenges a decision the ATO made about it.
- You forgot the Medicare exemption: amend
- You disagree with how the ATO assessed your residency: object
- The ATO has written proposing changes: respond with records rather than pre-emptively amending
Our guide to objecting to an ATO decision covers the second path, which has its own deadlines and structure.
What happens to your money?
If the amendment increases the refund, the additional amount is paid to your nominated account, generally within a few weeks to a couple of months. If it reduces the refund, the ATO issues a revised assessment and the difference becomes payable, usually within 21 days.
An amendment that adds forgotten income creates a debt, and it is still the right thing to do. The alternative is the ATO finding it through data matching and adding interest and a penalty to the same amount.
Does amending draw attention to you?
No. Amendments are an ordinary part of the system, and a genuine correction supported by records is not a flag. Voluntary disclosure of an error is treated more favourably than the same error found by the ATO.
A pattern of large unsupported claims is a different thing entirely. A single amendment adding a Medicare exemption or a forgotten set of work boots is invisible.
Can you amend after leaving Australia?
Yes. The two year window applies wherever you are. Amendments are lodged remotely and any additional refund pays into an Australian account.
The account is the practical constraint, not the amendment. Where the Australian account has been closed, arranging an alternative payment route adds time, so it is worth keeping the account alive until the year is genuinely finished rather than until you fly.
What decides whether an amendment is worth lodging?
Two things: the size of the correction and whether it can be substantiated. An amendment for a $40 deduction with no receipt is not worth the time. Adding a Medicare Entitlement Statement to a year where the 2% levy was charged is worth about $500 on $25,000 of earnings and takes the same effort.
The pattern in the returns we amend is consistent. Medicare exemptions unclaimed because the statement arrived late. Deductions overlooked because the receipts were in a different phone. ABN income reported in the wrong place. A period at 45% before the TFN landed that was never recovered. Almost all are upward, and almost all come from returns lodged quickly rather than completely. If you lodged a tax return yourself and it did not deal with residency, Medicare and every employer, it is worth a second look while the two years are still open.