Time limits on income tax amendments
The law sets time limits for amending your tax assessment.
For individuals and small businesses the time limit is generally two years, and for other taxpayers four years, from the day after we give you the notice of assessment for the year in question (generally taken to be the date on the notice or, if we don't issue a notice, the date the relevant return was lodged).
For example, you're a sole trader and receive a notice of assessment dated 12 November 2015. Your two-year amendment period starts on 13 November 2015 (the day after the date on the notice) and ends two years later, on 12 November 2017, so you have until that day to lodge a request for an amendment to that assessment.
You can submit more than one amendment request within a period of review.
The time limit gives you certainty about your tax affairs because it means we can't amend your tax assessment after the time limit has passed (except in some exceptional situations such as evasion or fraud).
If you want to change a tax return after the time limit has passed you can't request an amendment, but you may be able to lodge an objection. While the time limit for lodging amendments and objections is the same, you can request an extension of time to lodge an objection in some circumstances.
There are time limits for amending your tax assessment – generally two years for individuals and small businesses and four years for other taxpayers. Beyond this time you may be able to lodge an objection instead.