Capital gains tax (CGT) calculator for Australian investors

by Angela Thompson, Senior Digital Marketing Manager, Sharesight | Jun 15th 2023
Disclaimer: The below article is for informational purposes only and does not constitute a specific product recommendation, or taxation or financial advice and should not be relied upon as such. While we use reasonable endeavours to keep the information up-to-date, we make no representation that any information is accurate or up-to-date. If you choose to make use of the content in this article, you do so at your own risk. To the extent permitted by law, we do not assume any responsibility or liability arising from or connected with your use or reliance on the content on our site. Please check with your adviser or accountant to obtain the correct advice for your situation.

In Australia, when investors sell shares and other listed securities for a price higher than they paid, the profit or capital gain may be subject to a capital gains tax (CGT). CGT is common globally, but Australia’s implementation is considered one of the world’s most complex, and the nuance in this regulation can have significant implications at tax time. As a result, investors must understand how their trading activity during the year will impact their capital gains position in their tax return at the end of the financial year. To learn more about CGT and how you can automatically calculate your CGT with Sharesight, keep reading.

Capital gains tax (CGT) calculator Sharesight

What is capital gains tax (CGT)?

If an investor sells an investment for more than the cost to acquire it, they have realised a capital gain. This will need to be reported in their annual income tax return. Although it’s referred to as capital gains tax (CGT), this is actually part of the income tax regime and not a separate tax.

Because capital gains are added to assessable income and are taxed at the marginal income tax rate, this may increase the tax an investor needs to pay and reduce the net return from investing significantly. As tax is not withheld for capital gains like it is for PAYG employee income, it is a good idea for shareholders to work out how much is likely to be owed on an ongoing basis and set aside sufficient funds to cover this.

While investors need to include all capital gains in their tax return for the year they sell the shares, a discount applies for longer-term investments. Investments held for more than 12 months are only taxed on half of the capital gain. This is known as the capital gains tax (CGT) discount. Investors must also be mindful that capital gains can be offset against capital losses when calculating CGT, with investors sometimes adopting what is known as tax loss selling in order to net out their capital gains where practical.

CGT events affecting shares

Generally investors have to pay tax on any capital gain they make on shares or units when a CGT event occurs, most commonly when an investor chooses to sell shares they own. However, a CGT event is also triggered when the change of ownership of an investment is involuntary.

One example is when a company in which an investor holds shares is acquired by, or merges with another company. This may result in a capital gain or loss. A CGT event may also occur when an investor:

  • Switches units in a managed fund to another fund

  • Receives a distribution (other than a dividend) from a unit trust or managed fund

  • Receives non-assessable payments from a company

  • Owns shares in a company that has been placed in liquidation or administration.

Calculating the cost base of investments for CGT in Australia

When selling part of a shareholding where investors have bought multiple parcels over time at different prices, several factors need to be considered. For example, investors will need to be able to identify and nominate exactly when the shares of the holding they’ve sold were purchased to determine the cost base, as this will affect the realised capital gain or loss and any CGT discount that applies. The cost base of a CGT asset is generally the cost when bought by the investor, plus certain other costs associated with acquiring, holding and disposing of the asset.

Note: Where an investor cannot identify when a bundle of shares were purchased, the ATO allows for a "first in, first out" (FIFO) method and average cost method in certain circumstances.

ATO methods to calculate capital gains

There are potentially three methods by which Australian investors can calculate their capital gains tax. It helps to be organised and have an exact record of when each shareholding was bought or sold. Here’s how the three methods may be applied.

CGT discount method: Generally, investors adopt the CGT discount method for investments held for more than 12 months, and the other methods for investments held for less than 12 months. Individual investors can get a 50% discount on their capital gains – once capital losses have been added – if they owned their shareholdings for more than 12 months before selling them.

Indexation method: This method is available to investors if the shares were acquired before 21 September 1999 and they have owned them for 12 months or more before a CGT event. The indexation factor is worked out using the consumer price index (CPI) as a multiplier to account for inflation. This may be an option for investors who are carrying forward any capital losses for assets held before September 1999.

Other method: The ‘other’ method is the simplest of the three methods for calculating a capital gain. This method is applied if investors have held shares for less than 12 months before the CGT event. This method is applied by subtracting the cost base from the capital proceeds, with the remainder being the capital gain (or loss).

Calculate your portfolio CGT with Sharesight

Manually calculating the CGT on your investment portfolio can quickly become complex and subject to error. If you’re looking for an easy way to calculate your CGT, you’ve come to the right place. Sharesight’s award-winning investment portfolio tracker includes a powerful Australian capital gains tax report that functions as a CGT calculator, determining capital gains made on sold shares as per Australian Tax Office (ATO) rules.

You may run the report over any period to see:

  • The CGT position for all your holdings sold within the period.

  • Your CGT gains broken up into short and long term, as well as your losses.

  • A summary of the short and long-term gains and losses, as well as any capital gain or claimable loss.

Capital gains tax report Australia

Designed for Australian tax requirements

The capital gains tax report uses the 'discount method' for shares that have been held for more than a year and the ‘other method’ for shares held for less than a year. The discount rate is based on the Australian tax settings you select when setting up your portfolio:

  • Individuals / Trust – CGT discount of 50 %

  • Self Managed Super Fund – CGT discount of 33⅓ %

  • Company – CGT discount of nil

Change your sale allocation methods

The capital gains tax report also allows you to specify the sale allocation method at the overall portfolio and individual holding level to determine your optimum position, including:

  • First In, First Out (FIFO) – Sharesight assumes that you sell your longest held shares first.

  • Last In, First Out (LIFO) – Sharesight assumes that you sell your most recently purchased shares first.

  • Minimise Gain – Sharesight assumes that you sell shares with the highest purchase price first.

  • Maximise Gain – Sharesight assumes that you sell shares with the lowest purchase price first.

  • Minimise CGT – Sharesight assumes that you sell shares that will result in the lowest capital gains tax first. This method is more sophisticated than the ‘Minimise capital gain’ method because it takes into account the Australian CGT discounting rules.

The sale allocation method can be changed for specific holdings or for the entire portfolio:

Sale allocation methods CGT report

Share the report with an accountant

The ability to download the report into an Excel spreadsheet, PDF or Google Sheet makes it easy to share this report with your accountant – potentially helping you save time and money at tax time. You may also wish to securely share your full Sharesight portfolio with your accountant, which will give them real-time access to the portfolio, with the ability to see holdings, dividends, corporate actions and any trades that are made.

Need more information on the capital gains tax report?

If you’re looking for more information on how to use Sharesight’s capital gains tax report, see our Help page or view our video walkthrough:

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To get started for FREE, simply sign up, import your holdings and watch as dividends and prices are automatically updated. If you decide to upgrade, you’ll unlock advanced features and everything you need to run your tax reports and gain unparalleled insights into your portfolio performance throughout the year.

Plus, as an Australian tax resident, you can save even more by claiming your Sharesight subscription fees on your tax return.1



1 If you derive income from the share market, your Sharesight subscription may be tax deductible. Check with your accountant for details.

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