Help Centre CGT Calculator

Using the CGT Calculator.

Tax guide· FIFO · 50% discount · P&L export· Essential plan and above
Tax information only. Not tax advice. PortWorth's CGT calculator provides indicative figures for planning purposes. It does not account for all circumstances. Always consult a registered tax agent (RTA) or accountant before lodging your tax return.

How CGT works in Australia: a quick primer

When you sell shares for more than you paid, the profit is a capital gain. If you held the shares for more than 12 months, only 50% of the gain is taxable — the CGT discount. That discounted amount is added to your assessable income and taxed at your marginal rate.

Capital losses (selling for less than cost) offset capital gains. Unused losses carry forward indefinitely to offset future gains. Losses cannot reduce your income below zero.

How PortWorth calculates CGT: FIFO matching

PortWorth uses the FIFO (First In, First Out) method: when you sell shares, the oldest parcels are matched to the sale first. This is the most common method in Australia and is accepted by the ATO as the default approach.

FIFO example You buy 100 CBA at $80 in June 2022, then 100 more at $110 in March 2024. In September 2025 you sell 100 shares at $130. FIFO matches the sale to the June 2022 parcel: gain = (100 × $130) − (100 × $80 + $9.95) = $4,990. Held 39 months, so the 50% discount applies: taxable gain = $2,495.

Step 1: Enter your full trade history

The CGT calculator only produces correct results if every trade is entered. Missing a buy trade inflates the apparent gain; missing a sell creates phantom holdings. Enter trades as described in the Record a Trade guide, working from your oldest trade forward.

Step 2: Open the CGT report

  1. Go to Analysis → Performance in the main navigation.
  2. Select the Tax / CGT tab.
  3. Choose the financial year from the dropdown (e.g. FY 2024–25). Australian financial years run 1 July to 30 June.
  4. The report generates immediately from your trade log, no extra input needed.

Step 3: Read the CGT report

The report has two sections:

Disposal details table — every sale in the year with:

  • Ticker, sale date, units, proceeds
  • Matched buy parcel(s) date, cost base
  • Gross capital gain or loss
  • Whether the 50% discount applies (held > 12 months)
  • Net CGT gain after discount

Summary — totals showing:

  • Total gross capital gains
  • Total capital losses
  • Net gain after losses (before discount)
  • Discounted gain (after 50% discount where applicable)
  • Estimated tax payable at 47% marginal rate
47% estimate The 47% estimate (45% top rate + 2% Medicare Levy) is a worst-case indicator. Your actual tax depends on your total taxable income, which determines your marginal rate. Use it to understand the order of magnitude of your CGT liability, then discuss with your accountant.

Step 4: Export for your accountant

Once you have reviewed the report, download it in the format your accountant needs.

Downloading the CGT report as a PDF

  1. Open Analysis, then Performance, then select the Tax / CGT tab.
  2. Select the financial year from the dropdown.
  3. Click Export PDF. A formatted CGT summary downloads immediately, ready to email directly to your accountant. The PDF includes your name, the financial year, the full disposal table with FIFO-matched parcels, the CGT summary totals, and the estimated tax figure.

Downloading the CGT report as a CSV

  1. On the same Tax / CGT tab, click Export CSV.
  2. The CSV opens in Excel, Numbers, or Google Sheets. Each row is one disposal event with columns for: ticker, sale date, units, proceeds, cost base, gross gain/loss, discount applied (Y/N), and net CGT gain.
  3. Accountants using Xero Tax, CCH, or MYOB can import this directly or use it to cross-check their own calculations.
Save your accountant time. Send the PDF before your tax appointment. It contains all the CGT workings they need. If they use tax software, the CSV saves them re-entering every trade manually.

Tax-loss harvesting before 30 June

If you have capital gains for the year, you can reduce your liability by selling holdings currently in a loss position before 30 June. These capital losses offset the gains directly. The Portfolio X-Ray and Performance tabs show your unrealised gains and losses — look at the "Unrealised P&L" column to identify candidates.

Wash sale rule The ATO may challenge "wash sales" — selling to crystallise a loss and immediately rebuying the same stock. If your sole purpose was to create a tax benefit, the transaction may be disregarded under general anti-avoidance provisions. Seek tax advice before implementing a tax-loss harvesting strategy.

Frequently asked questions

Does PortWorth support the LIFO or average cost method?

Currently PortWorth uses FIFO only, which is the ATO default. LIFO is not commonly used in Australia. Average cost is used by some managed funds. If your accountant uses a different method, the CSV export gives the raw trade data for them to recalculate.

How are crypto capital gains calculated?

The same FIFO method applies to crypto. Every disposal (sale, swap, or use of crypto to purchase goods) is a CGT event. Enter each transaction in the Crypto tab with the AUD value at the time. Crypto-to-crypto swaps are treated as disposal of one asset and acquisition of another — record each leg separately.

Are franking credits factored into CGT?

Franking credits are not a CGT matter — they are an income tax offset. They do not affect cost base. PortWorth tracks franking credits on the Dividends panel separately. Your accountant combines the franking credit offset with your CGT on your tax return.

What about property CGT?

Property CGT (for investment properties, not your principal place of residence which has its own exemptions) is tracked on the Property tab when you record a sale. The same FIFO and 50% discount rules apply. The CGT report covers all asset classes including property disposals.

Tax time, simplified.

Your CGT report, ready to export.

PortWorth generates a complete FIFO-matched CGT P&L for every financial year. Join the waitlist.