How to Amend an Australian Tax Return After You Have Lodged It

When should you amend a lodged tax return?

An amendment is the normal way to correct an individual tax return when you realise after lodging that information was wrong, incomplete or later needed to be changed. Typical examples include omitted income, an incorrect income amount, a missed deduction, an incorrect tax offset, spouse information or another mistake in the lodged return.

The Australian Taxation Office advises you to wait until the original tax return has been processed before lodging an amendment. Lodging another transaction while the original return is still being processed can complicate or delay the process.

You do not need to lodge an entirely new tax return unless the ATO specifically asks you to. An amendment changes the assessment for the income year concerned.

How long do you have to amend a tax return?

For most individuals and sole traders, the amendment period is generally 2 years. The period starts on the day after the ATO sends your notice of assessment.

For example, if a notice of assessment is dated 1 November 2024, the amendment period begins on 2 November 2024 and ordinarily ends on 1 November 2026.

You can submit more than one amendment during the applicable amendment period if further corrections are genuinely required.

If the normal amendment period has expired, you generally cannot obtain an extension simply to lodge an ordinary amendment. Depending on the circumstances, you may instead be able to lodge an objection, including a request for an extension of time to object. Certain tax rules also provide specific extended amendment periods for particular situations.

How to amend your tax return online

You can amend an individual tax return through ATO online services linked to myGov, regardless of whether the original return was lodged online, on paper or through a tax agent.

1. Sign in to your myGov account.
2. Select the Australian Taxation Office from your linked services.
3. From the ATO home page, select Manage tax returns. An alternative navigation path is Tax, then Lodgments, Income tax, then the History tab.
4. Select the income year you need to correct.
5. Select the available amendment option.
6. Review the lodged information and change the relevant sections.
7. Check the amended return carefully and submit it.

The online service can display previously lodged information, allowing you to correct the relevant entries rather than recreate the entire return from scratch.

Review all affected figures before lodging

A correction to one item can affect other calculations in the return. Before submitting, review the complete amended position for that income year and make sure the figures are supported by your records.

Keep the evidence needed to substantiate the amendment. The amendment system forms part of Australia's self-assessment system, so responsibility for the accuracy of the information remains with you.

Can you amend while another amendment is being processed?

If an amendment you requested, or an amendment initiated by the ATO, is already being processed, the online service may prevent you from lodging another amendment for that income year.

The ATO states that the online amendment option becomes available again after the existing amendment reaches the relevant processed or issued status, provided you are still within the applicable amendment time limit.

If you have made multiple discoveries, it is usually more practical to gather the complete corrected information before lodging rather than sending overlapping amendments.

How long does an amendment take to process?

An online amendment generally takes about 20 business days to process. An amendment submitted in writing can take up to 50 business days.

You can monitor progress through ATO online services. From the home page, select Manage tax returns and then choose the financial year you want to check.

If the ATO needs further information to deal with the amendment, it may contact you, which can increase the total elapsed time.

What happens after the amendment?

Once the ATO processes the amendment, it issues a notice of amended assessment. This shows the revised tax outcome for that income year.

The amendment may result in an additional refund, a reduced refund, additional tax to pay or no change to the amount payable, depending on the corrected information. If a refund is due, the ATO uses the bank account details held for the relevant payment process, so keeping your payment details current helps avoid delays.

Other ways to request an amendment

If you cannot or do not want to amend online, the ATO also permits other methods.

• Registered tax agent: your tax agent can lodge an amendment electronically through the Practitioner Lodgment Service.
• Paper form: individuals can use the ATO Request for amendment of income tax return for individuals form.
• Letter: you can send a written amendment request containing all required information and supporting material.

Written amendments take longer than the online route, with the ATO publishing a processing period of up to 50 business days.

What must a written amendment include?

A written request should clearly identify you, the income year and the exact changes requested. The ATO requires relevant details such as your TFN, full name, contact information, the tax return question or item being changed, the income, deductions or offsets being added or removed, the corrected totals, an explanation for the change and the required signed declaration. Keep a copy of anything you send.

When an amendment is not the right process

An amendment is intended mainly to correct an error or omission. If you are disputing how the ATO applied the law, challenging an ATO decision or seeking review of an adjustment made following an audit, an objection may be the appropriate procedure instead.

You may also need to consider an objection when the ordinary amendment time limit has expired. The amendment and objection processes have different legal consequences, so use the procedure that matches what you are actually asking the ATO to change.

Common amendment mistakes to avoid

• Submitting an amendment before the original return has finished processing.
• Waiting until after the standard 2-year amendment period without checking whether an objection is required.
• Changing one figure without checking whether related sections of the return also need correction.
• Claiming a deduction or offset without keeping appropriate supporting records.
• Submitting repeated amendments while an earlier amendment is still processing.
• Using an amendment when you are actually disputing an ATO decision that should be dealt with through the objection process.
• Sending another complete tax return instead of an amendment when the ATO has not asked you to do so.