You lodge your tax return, receive your notice of assessment, and then notice something is wrong. Perhaps you forgot to include bank interest, entered an incorrect income figure or missed a deduction you were entitled to claim. These situations are more common than many Australians often realise. During the 2024-2025 financial year, the ATO adjusted more than 595,000 individual tax returns due to certain discrepancies.
This blog will help you check what went wrong and follow the correct ATO amendment process when you spot a tax return mistake in Australia:
Making an error does not always mean that you will face a penalty. However, leaving it uncorrected can create problems later. You have to amend tax return in Australia if the mistake affects your taxable income, deductions or tax payable.
Before you amend anything, it is necessary to identify where the tax return mistakes most commonly occur for everyday Australian taxpayers.
Income information can be entered incorrectly for numerous reasons. You might forget to consider a second job, enter a figure incorrectly or overlook interest earned from a bank account. Sometimes, information might also change after you have started preparing your return. If your reported income does not match the information available to the ATO, the return might have to be corrected.
You might have paid for expenses related to your job but forgotten to include them. This can happen with work-related travel, professional membership, tools or other eligible costs. Not every work expense is deductible, though. You need to meet the relevant ATO requirements and retain appropriate records before claiming it.
A common mistake is assuming that anything purchased for work can be claimed. Personal expenses cannot become deductions suddenly because they were useful at work. For example, an expense may need to have a direct connection with earning your income. Claiming something without meeting the requirements can affect your tax outcome and may create additional issues.
A simple typing mistake can affect how your return is processed or where your refund is paid. Therefore, it is essential to check your bank account details, address, contact information, and other personal details before submitting your return. Moreover, updating incorrect information in a timely manner can prevent avoidable delays and confusion.
Here are some of the most frequently used ways through which you can fix your mistake:
If you notice an error before your original return has been processed, do not immediately submit an amendment. The ATO advises waiting until you receive confirmation that the original return has been processed. Once it has been processed, you can use the amendment process to correct missing income, incorrect answers, deductions, offsets or other associated information.
After your tax return has been processed, you can request an amendment if you discover an error or omission. First, check your original return and supporting records. The correction might increase your refund or result in additional tax payable.
You have several ways to correct a processed tax return. Also, the option has to be chosen on the basis of your circumstances and should be supported by records.
The timeframe for a prior year tax return amendment depends on how you submit the request and the type of amendment involved. Given here is a table that provides clarity on the subject:
| Amendment Method | Processing Time | Important Information |
| Online through ATO online services | About 20 days | Available through myGov or the ATO app. Your myGov account must be linked to the ATO. |
| Paper amendment form | Up to 50 business days | Used when you cannot request an amendment online. The completed form must be signed. |
| Through a registered tax agent | Up to 50 business days for written requests | Tax agents can lodge amendments electronically through the Practitioner Lodgment Service. |
| By sending a letter | Up to 50 business days | The letter must include relevant details and supporting documents. |
| Amendment time limit for individuals | Generally 2 years | The period starts on the day after the notice of assessment is sent. |
| Amendment time limit for sole traders | Generally 2 years for 2023-24 and earlier; 4 years for 2024-25 onwards | The period begins on the day after the assessment is sent. |
Adequate records make it easier to explain your correction and back up your amendment request.
With the assistance of a tax return correction service in Perth, these records can be kept organised and accurate.
Yes, correcting an error can change the amount you receive from the ATO. If the amendment reduces the tax you owe, you might receive a larger refund, provided you have no other tax debts. If the correction increases your tax liability, you will have to pay additional tax. In such cases, help from tax return services in Perth can enable you to understand the outcome better.
Speaking with a tax accountant can be useful when a tax mistake is unclear or could affect your final tax position.
Palladium Financial Group can help you review an incorrect return, identify information that requires changing and prepare the relevant amendment. Their team can verify the supporting records and explain the likely tax outcome with transparency. Hence, when you need to lodge amended tax return in Perth, professional assistance can make the process easier to manage.
Also read: Claimed the Wrong Tax Deduction? Here’s What to Do Next
A mistake on your tax return does not always hint at a major problem, but leaving it uncorrected can affect your final tax position. Therefore, check your records, have some patience till the original return is processed and use the appropriate amendment method. When the situation is indeed complicated, expert guidance can save you from the confusion. If you need help correcting errors, a tax accountant in Perth can prepare the necessary amendment for you and take you through the process.
Yes. Receiving your tax refund does not generally prevent you from requesting an amendment. If you later discover that information in your return was incorrect or incomplete, you can request a correction through the appropriate ATO amendment process. The amendment may result in an additional refund or an amount of tax becoming payable.
Yes, you may be able to amend a tax return more than once if further errors or omissions are identified. Each amendment should be based on accurate information and supported by relevant records. If multiple amendments are required, particularly for a complex return, professional tax advice can help ensure the changes are reported correctly.
An amendment does not automatically mean that the ATO will audit your tax return. However, the ATO may review information where an amendment raises questions or does not align with information available to it. Providing accurate information and keeping appropriate supporting records can help demonstrate that the amendment has been made for a legitimate reason.
If an amendment increases your taxable income or reduces your deductions, your tax liability may increase. The ATO will issue an amended notice of assessment showing the revised amount. You will generally need to pay any additional tax by the relevant due date, although payment arrangements may be available in some circumstances.
It depends on the circumstances. If an ATO review has identified an issue, you should consider the information provided by the ATO before making any changes. An amendment may be appropriate where you have identified an error in your original return, but some situations may require you to respond directly to the ATO rather than simply lodging an amendment.
If you discover another mistake after submitting an amendment, you should review the information and determine whether another amendment is required. Avoid submitting repeated corrections without checking the underlying records. For complicated tax matters, a registered tax agent can review the return and help determine the appropriate correction.
An amendment can affect information relevant to your future tax position, depending on what was changed. For example, changes to income, deductions or other tax-related information may influence calculations in later years. However, amending an earlier return does not automatically mean that your future tax returns will need to be changed.
You may be able to amend an older tax return, but amendment time limits can apply and may vary depending on your circumstances. Before submitting a request for an older income year, check whether the amendment period still applies. If the return is outside the usual amendment period, you may need to contact the ATO or seek professional tax advice.
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