The instant asset write-off lets an eligible small business immediately deduct the full cost of a qualifying asset in the year it is first used, rather than depreciating it over years. The catch that trips up firms is that the threshold has been a moving target for over a decade, set year by year and often legislated only weeks before the previous window expired. That makes this an area where the single most important thing is not memorising a number, it is knowing the legislative status for the income year you are actually claiming in, because the threshold that applied last year may not be law for this one. Get that wrong and the client either misses a deduction they were entitled to, or claims one that no longer exists.
The rules, and why the year matters more than the number
The write-off is available to businesses with aggregated turnover under $10 million that use the simplified depreciation rules, and it applies per eligible asset first used or installed ready for use for a taxable business purpose within the income year. Both new and second-hand assets qualify. The threshold itself is where the care is needed. The $20,000 threshold was law for the 2025-26 income year under legislation that has passed, so claims for assets first used by 30 June 2026 sit on settled ground. For 2026-27 and beyond, the position is different and must be checked rather than assumed. The Government announced in the May 2026 Budget that it intends to make the $20,000 threshold permanent from 1 July 2026, but as an announcement is not law, that measure has to pass Parliament before it takes effect. Until it does, the standing legislated threshold reverts to $1,000. So for any asset first used from 1 July 2026, the correct first step is to confirm the current legislative status on the ATO site, because the answer determines whether a $15,000 machine is written off in full or pooled and depreciated. This is not hedging, it is the actual state of the law, and it is exactly the kind of thing a firm is expected to get right.
Two mechanics apply regardless of the threshold in force. The limit is GST-exclusive for a registered business, so a client registered for GST who buys an asset with a GST-inclusive price strips out the GST first, tests the GST-exclusive figure against the threshold, and claims the GST separately as an input tax credit on the BAS. A client not registered for GST uses the full GST-inclusive price. And the threshold applies to the full cost of the asset, not the deductible portion, so an asset costing more than the threshold does not qualify even if the business-use percentage would bring the deductible amount below it. In that case the asset goes into the small business pool, depreciated at 15% in the first year and 30% thereafter.
Where the coding errors happen
Vehicles cause the most trouble. A passenger vehicle, meaning one designed to carry fewer than nine passengers with a load capacity under one tonne, is subject to the car limit, which caps the value you can use to calculate depreciation and is indexed by the ATO each income year, so the correct figure is always the one for the year the car was first used, not a number carried over from last year. Because a passenger car worth more than the write-off threshold cannot be instantly written off anyway, it goes into the depreciation pool with its cost capped at the car limit. A commercial vehicle with a payload over one tonne, such as most tradies' utes and vans, is not subject to the car limit and can be written off in full if its cost is under the applicable threshold. The second consistent error is treating the purchase date as the qualifying event rather than the use date. An asset ordered in one income year but delivered and installed in the next does not qualify for the earlier year, because the rule is first used or installed ready for use within the income year. For anything needing shipping, commissioning or installation, that distinction is where end-of-year purchases quietly miss the window when delivery slips. The third error is folding the income tax write-off and the GST credit together. They are separate claims: the write-off goes in the income tax return on the GST-exclusive cost, the GST credit goes on the BAS for the period of purchase, and coding the full GST-inclusive amount as the deductible figure creates an error that spans both the return and the BAS.
The four questions to answer before processing a claim
Before any instant asset write-off claim goes through, four questions settle it. Is the business's aggregated turnover under $10 million and is it using the simplified depreciation rules? What threshold is actually in force for the income year the asset was first used, confirmed against current ATO guidance rather than assumed from last year? Is the asset's cost under that threshold on a GST-exclusive basis for a registered business? And if it is a vehicle, is it a passenger vehicle caught by the car limit or a commercial one that is not? Answering those four before the claim is processed, rather than after the ATO asks, is what keeps the deduction defensible. The threshold will keep moving, and the car limit will keep re-indexing, so the durable skill is not remembering this year's figures. It is checking them every time, for the year that actually applies.
