What should I do if I disagree with my tax assessment?
Understand your options if you disagree with your Notice of Assessment or another ATO decision.
Summary
If you disagree with an ATO decision, you can dispute or lodge a formal objection. There is no fee to lodge an objection, but there are time limits.
What this means
You may disagree with your Notice of Assessment, an amended assessment, or another decision made by the ATO. Options include contacting the ATO to discuss the decision, requesting an amendment where appropriate, or lodging a formal objection.
Time limits for objecting depend on the type of decision and your circumstances and may be 60 days, 2 years or 4 years. If you are unhappy with the outcome of an objection, further options may include external review through the Administrative Review Tribunal or the Federal Court.
Typical actions
- Read the ATO's decision carefully and identify what you disagree with.
- Gather supporting information such as records, receipts and any relevant references.
- Check the time limits that apply to your situation.
- Consider whether an amendment or a formal objection is the right pathway.
- Speak with a registered tax agent or legal professional if the matter is complex.
Official ATO sources
Last checked: 24 August 2026
If you disagree with an ATO decision
Main hub for options if you disagree with an ATO decision.
Object to a decision
Explains the formal objection process.
Steps to lodge an objection
The step-by-step objection process, including time limits.
Dispute a decision
Wider dispute pathways, including independent review options.
Related questions
- What is a Notice of Assessment?
- How do I amend a tax return?
- Do I need to use a tax agent to lodge my return?
- What is a tax return?
Important notice: Tax Clarity is an independent information tool. This page provides general information based on official sources. It does not provide tax, legal, financial, or accounting advice. Tax rules can change, and how they apply depends on your circumstances. For advice about your situation, speak with a registered tax agent or qualified professional.
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