After you lodge your tax return, the Tax Office sends you a notice of assessment. This outlines your taxable income and tells you how much tax you need to pay or how much refund you are getting. If you are a partnership, company or trust, the tax return itself can be the notice of assessment unless it is amended by the Tax Office.
The notice of assessment is an important document, and a key part of that notice is the date on which it issued. This is because the Tax Office has a limited time in which to amend the assessment and, perhaps, call on you to pay more tax.
The time period in which a notice of assessment can be amended is either 2 years or 4 years from the date the notice was issued. This depends on the type of taxpayer you are. Generally, where a small or medium business is involved, the amendment period is 2 years. A small business has a turnover of less than $10 million and a medium business has a turnover of less than $50 million.
There are circumstances where the Tax Office can amend a notice of assessment outside the 2- or 4-year period.
These include:
Where there is fraud or evasion.
To give effect to a decision on a review or appeal (AAT or a court).
As a result of an objection made by a taxpayer or pending a review or appeal.
The taxpayer applies for an amendment in the approved form prior to the amendment period ending.
Where the taxpayer has applied for a private ruling before the amendment period has finished and the ATO amends the assessment to give effect to the private ruling.
The ATO requests a taxpayer to extend the amendment period and the taxpayer consents to the extension.
