Australia Does Not Have a Wash Sale Rule
If you have read US-focused trading forums, you have probably come across the "wash sale rule" -- the IRS regulation that disallows a capital loss if you buy the same or substantially identical security within 30 days before or after the sale. It is a bright-line rule. Sell at a loss and repurchase within the 30-day window, and the loss is deferred until you finally dispose of the replacement shares.
Australia has no equivalent rule. There is no legislated waiting period, no automatic disallowance, and no specific provision in the tax code that targets the pattern of selling and repurchasing the same stock.
But that does not mean you can sell shares at a loss on Monday, buy them back on Tuesday, claim the capital loss on your tax return, and expect the ATO to accept it without question.
Part IVA: The General Anti-Avoidance Provision
What Australia has instead is Part IVA of the Income Tax Assessment Act 1936 -- the general anti-avoidance provision. Part IVA gives the Commissioner of Taxation the power to cancel tax benefits obtained from schemes entered into for the dominant purpose of obtaining a tax benefit.
The language is deliberately broad. A "scheme" includes any arrangement, agreement, understanding, promise, or undertaking -- whether formal or informal, express or implied. A single transaction can be a scheme.
The ATO has specifically addressed wash sales in Taxation Ruling TR 2008/1, which provides guidance on applying Part IVA to arrangements where a taxpayer sells a CGT asset at a loss and reacquires the same or substantially similar asset shortly after.
How the ATO Identifies Wash Sales
The ATO published Taxpayer Alert TA 2008/7 specifically targeting wash sale arrangements. The alert describes the pattern: a taxpayer disposes of a CGT asset, realises a capital loss, and shortly afterwards reacquires the same or substantially similar asset, with no significant change in their economic exposure.
The ATO's data-matching capabilities are extensive. They receive transaction data directly from share registries, brokers, and crypto exchanges. Identifying a sale-and-repurchase pattern on the same security within a short window is a straightforward data query.
When assessing whether Part IVA applies, the ATO considers eight factors under section 177D, including: the manner the scheme was carried out, its form and substance, the timing, the result without the scheme, and any change in financial position. The critical question is whether the dominant purpose of the arrangement was to obtain a tax benefit. Not a purpose. Not a significant purpose. The dominant purpose.
What Makes a Sale Legitimate vs Suspect
The distinction comes down to whether you had a genuine commercial reason for the sale that exists independently of the tax benefit.
Lower Risk: Genuine Commercial Reasons
Portfolio rebalancing. You are overweight in one sector and sell to reduce exposure, then later re-enter when your allocation model signals an opportunity. The reason for selling is portfolio construction, not tax.
Strategy change. A stock no longer meets your entry criteria due to deteriorating fundamentals or a broken technical setup. You sell. Weeks later, the situation improves and you re-enter based on fresh analysis.
Stop loss triggered. Your pre-defined risk management rules forced the exit. The capital loss is incidental to the risk management purpose.
Switching between genuinely different assets. Selling BHP.AU at a loss and buying RIO.AU is not a wash sale -- they are different companies. Selling a Vanguard Australian Shares ETF (VAS) and buying a BetaShares equivalent (A200) is murkier, because the economic exposure is nearly identical.
Higher Risk: Patterns the ATO Targets
Same-day or next-day repurchase of the same stock. You sell 1,000 shares of WBC.AU at a loss on 25 June and buy 1,000 shares of WBC.AU on 26 June. Your position is unchanged, but you have crystallised a loss. This is the textbook pattern.
Pre-arranged repurchase. You sell with a standing order or commitment to repurchase. The ATO looks at whether the sale and repurchase were part of a single plan.
End-of-financial-year loss harvesting with immediate repurchase. Selling loss-making positions in late June and repurchasing in early July purely to realise losses while maintaining the same portfolio.
Cross-entity manipulation. Selling from your personal account at a loss and repurchasing through your SMSF or family trust to maintain the same economic exposure.
How This Differs from US Wash Sale Rules
The US has a bright-line rule under IRC Section 1091: buy the same or substantially identical security within 30 days before or after selling at a loss, and the loss is deferred (added to the cost base of the replacement shares). Wait 31 days, and you are clear. The consequence is deferral, not permanent denial.
Australia's approach is the opposite in almost every respect. There is no fixed waiting period, no automatic trigger, and no safe harbour. The consequence under Part IVA is that the loss is denied entirely -- not deferred. A repurchase after 60 days could be challenged if the ATO determines the dominant purpose was tax-driven, while a repurchase after 5 days might be acceptable if you have a documented commercial reason.
The US system gives certainty at the cost of rigidity. The Australian system gives flexibility at the cost of unpredictability.
The 45-Day Holding Rule Is Separate
Some traders confuse wash sale issues with the 45-day holding period rule for franking credits. These are entirely different provisions.
The 45-day rule determines whether you can claim franking credits on dividends. It requires you to hold shares "at risk" for at least 45 days to claim the franking credit attached to a dividend. It has nothing to do with capital losses, Part IVA, or wash sales.
You can sell a stock at a loss after holding it for 3 days and the 45-day rule is irrelevant. The question is whether Part IVA applies to the loss, which depends on your purpose for selling, not your holding period.
Tax-Loss Harvesting: Legal When Done Properly
Tax-loss harvesting -- deliberately realising capital losses to offset gains -- is legitimate. The ATO does not object to selling a losing position to crystallise a loss. The problem arises only when you sell and repurchase to create a loss without genuinely exiting.
The sale must be real. You must accept the market risk of being out of the stock and be willing to not repurchase if the opportunity does not present itself again.
Practical Guidance for Active Traders
Document your reasons for every trade. A trade journal that records your entry and exit rationale gives you evidence of commercial purpose if the ATO ever asks. "Sold because the stock broke below the 50-day moving average and my strategy rules required an exit" is far stronger than having no record of why you sold.
Do not sell and repurchase the same stock within a few days purely to book a loss. If you are exiting a position, genuinely exit. If you want to maintain exposure to the sector, consider a different stock or ETF with genuinely different characteristics.
Be especially careful around 30 June. The end-of-financial-year period is when the ATO most closely scrutinises loss crystallisation. Selling multiple losing positions in late June and repurchasing in early July is a pattern their data systems flag automatically.
Keep records of your decision-making process. If you sell a stock and then re-enter weeks later, be able to explain what changed. "I sold because the earnings report was poor and re-entered after the August guidance update gave me confidence the thesis was intact" demonstrates genuine commercial decision-making.
If the sole reason for selling is to create a tax loss, do not repurchase the same stock. This is the simplest rule. If you are selling only because you want the tax loss, take the loss and move on. Invest the proceeds elsewhere. The ATO cannot challenge a genuine disposal followed by investment in a different asset.
Consequences If Part IVA Applies
If the Commissioner determines Part IVA applies: the capital loss is denied entirely (not deferred as in the US -- cancelled), penalties of up to 50-75% of the tax shortfall may apply, and interest charges accrue from the original due date.
The risk-reward is clear. The tax saving from a wash sale is modest. The downside includes loss of the deduction plus penalties and interest. For active traders generating legitimate losses through normal activity, there is no need to manufacture additional losses through wash sale patterns.
How SwingFolio Supports Compliance
Every trade logged in SwingFolio captures entry and exit rationale, strategy rules that triggered the trade, and the full timeline of the position. This creates a contemporaneous record of your decision-making that serves as evidence of commercial purpose. When you export your trade data for your tax return, the journal entries travel with the CGT calculations, giving your accountant -- or the ATO, if asked -- a clear picture of why each trade was made.
Disclaimer: This article is general information only and does not constitute financial, tax, or legal advice. Part IVA application involves complex legal analysis of individual circumstances. The ATO's assessment of dominant purpose is fact-specific and may differ from the general principles described here. Always consult a qualified tax professional or registered tax agent for advice about your specific trading activities. Refer to ATO Taxation Ruling TR 2008/1 and Taxpayer Alert TA 2008/7 for the Commissioner's published guidance on wash sale arrangements.