Share trading tax obligations in Australia
If you buy and sell shares in Australia, you have tax obligations that depend on how the ATO classifies your activity. Whether you are an investor or a trader, you need to understand what records to keep, what to report, and when to seek professional help.
This guide covers the key tax obligations for Australian share market participants, so you can stay compliant and avoid common mistakes.
Disclaimer: This article is for informational purposes only and does not constitute financial or tax advice. Consult a qualified tax professional for advice specific to your circumstances.
Investor vs trader: why it matters
The ATO draws a clear line between share investors and share traders, and the distinction has significant tax consequences.
Share investors
Most people who buy shares fall into the investor category. As an investor:
- Profits from selling shares are taxed as capital gains under the CGT rules
- You may be eligible for the 50% CGT discount if you hold shares for more than 12 months
- Capital losses can only offset capital gains (not other income)
- Dividends are assessed as income in the year they are received
Share traders
The ATO considers you a share trader if you carry on a business of buying and selling shares. Key indicators include:
- You trade with a business-like purpose and have a clear profit-making intention
- The volume and frequency of your transactions are substantial and regular
- You have a business plan or trading strategy that you follow consistently
- You spend significant time researching and executing trades
- The activity is your primary or a significant source of income
As a trader:
- Profits and losses from share sales are treated as ordinary income, not capital gains
- You are not eligible for the 50% CGT discount
- Losses can be offset against your other income (salary, business income, etc.)
- You can claim business-related deductions (software, subscriptions, home office)
- You may need an ABN and need to report through a business schedule
The ATO looks at the overall picture rather than any single factor. If you are unsure which category you fall into, consult a tax professional. Getting this wrong can result in underpaid tax and penalties.
Record-keeping requirements
The ATO requires you to keep records of every share transaction for five years after you dispose of the shares (or five years after the last CGT event, whichever is later). For shares you still hold, you must keep records for the entire period of ownership plus five years after selling.
What records to keep
For each share purchase and sale, you need:
- Date of purchase and sale
- Number of shares bought or sold
- Purchase price per share and total cost
- Sale price per share and total proceeds
- Brokerage fees and other costs associated with buying and selling
- Dividend statements showing amounts received and franking credits
- Corporate action details such as share splits, mergers, return of capital, and bonus issues
- DRP (Dividend Reinvestment Plan) records if you reinvested dividends into additional shares
These records are essential for calculating your cost base accurately. Without them, you may overstate or understate your capital gain, both of which can create problems with the ATO.
If you participated in a DRP, each reinvestment is treated as a separate acquisition with its own cost base and purchase date. Over several years, this can mean dozens of individual parcels for a single holding, all of which need tracking.
You can learn more about managing these records in our guide to viewing transaction history. To keep records current without manual data entry, you can forward broker confirmation emails to your portfolio's unique email address and TrackMyShares will parse and queue the transactions for your review.
What to report in your tax return
For investors
In your individual tax return, you report share-related income in several places:
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Capital gains schedule. Report all share disposals for the financial year, including proceeds, cost base, and the resulting gain or loss. If you held shares for more than 12 months, apply the 50% CGT discount to the net gain.
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Dividend income. Report the total dividends received at the "Dividends" label. Include the franking credits as a separate amount. The ATO pre-fills much of this from data reported by share registries, but you should verify the figures against your own records.
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Deductions. You can claim deductions for interest on money borrowed to purchase income-producing shares, and for the cost of managing your share investments (such as portfolio tracking subscriptions or financial advice fees).
For traders
If you are classified as a trader, your share income and losses go through the business section of your tax return. You report proceeds as business income and claim cost of shares sold as a deduction. The profit or loss flows through to your assessable income as ordinary income.
Timing rules
When is a CGT event triggered?
A CGT event occurs on the contract date (the date you agree to the sale), not the settlement date. For ASX trades, the contract date is the trade date, and settlement typically occurs two business days later (T+2).
This matters around the end of financial year. If you sell shares on 30 June, the CGT event is triggered in that financial year, even though settlement occurs in the new financial year.
The 12-month CGT discount
To qualify for the 50% CGT discount, you must hold the shares for more than 12 months from the date of acquisition to the date of the CGT event. The acquisition date is the contract date for the purchase.
For example, if you bought shares on 15 January 2025, you need to sell them on or after 16 January 2026 to qualify for the discount. Selling on 15 January 2026 means you have held them for exactly 12 months, which does not qualify. You need more than 12 months.
Dividend timing
Dividends are assessable in the financial year you receive them, which is the payment date (not the ex-dividend date or the record date). This means a dividend declared in June but paid in July falls into the next financial year.
Common mistakes
1. Not tracking DRP parcels
Every DRP reinvestment creates a new parcel with its own cost base. If you have been in a DRP for years, you could have dozens of parcels. When you sell, you need to match each parcel correctly. Many investors either forget about DRP parcels entirely or use a single averaged cost base, both of which are incorrect under ATO rules.
2. Forgetting brokerage costs
Brokerage is part of your cost base (when buying) and reduces your capital proceeds (when selling). Leaving it out means you overstate your capital gain.
3. Ignoring corporate actions
Share splits, consolidations, mergers, demergers, and return of capital events all affect your cost base. A return of capital, for example, reduces the cost base of your shares. If you ignore it, you will understate your gain when you eventually sell.
4. Misapplying the CGT discount
The 50% discount only applies to the net capital gain after you have applied all capital losses. Some investors mistakenly apply the discount before offsetting losses, which results in paying less tax than they should. The correct order is: calculate your capital gain, subtract capital losses, then apply the 50% discount to the remaining amount.
For a detailed walkthrough of how to calculate capital gains correctly, see our guide on how to calculate capital gains on shares in Australia.
5. Misclassifying investor vs trader status
Claiming trader status when you are really an investor (or vice versa) can lead to serious problems. The ATO audits this. If you claim ordinary losses against your salary income but the ATO determines you are an investor, you could face penalties and a reassessment.
When you might need a tax agent
Consider getting professional help if:
- You have a large number of transactions and are not confident in your record-keeping
- You have received corporate actions (mergers, demergers, return of capital) that affect your cost base and you are unsure how to handle them
- You are unsure whether you are an investor or a trader and the distinction affects your tax position significantly
- You have overseas shares that may involve foreign tax credits or currency conversion
- You have carried-forward capital losses from prior years and want to ensure they are applied correctly
- Your portfolio is held in an SMSF with specific reporting requirements
The cost of a tax agent is generally tax-deductible, and getting it right is far cheaper than dealing with an ATO reassessment.
How to report your tax obligations correctly
You can read more about the tax treatment of Australian shares in our guides on how much tax you pay on shares in Australia and how to calculate capital gains on shares.
Track your tax obligations with TrackMyShares
Keeping accurate records across years of investing is one of the biggest challenges for Australian shareholders. TrackMyShares helps by recording every transaction, tracking cost bases across multiple parcels (including DRP), and generating tax reports that summarise your capital gains, losses, and dividend income for each financial year.
If you trade through multiple brokers, you can import transactions from each one (with dedicated guides for CommSec, SelfWealth, Stake, and others) and use consolidated portfolios to view everything in a single combined report.
With all your records in one place, you can be confident that your tax return is accurate and that you have the documentation to support it if the ATO ever asks questions.