CGT events are the single most-common reason DIY filers should use a Tax Agent
If you sold, swapped, or otherwise disposed of shares, ETFs, managed funds, or cryptocurrency during FY2025–26 — even one trade — you have a Capital Gains Tax (CGT) event to report.
The reporting rules are nuanced, the calculations easy to get wrong in myTax, and the ATO (ATO guidelines) actively data-matches share registries + Australian crypto exchanges to spot omissions. This is one of the highest-ROI areas to use a Registered Tax Agent.
This guide explains why, and when DIY is still viable.
What myTax requires you to do for shares and crypto
For every disposal event, you must:
For each individual asset disposed. If you traded actively, that's potentially dozens or hundreds of calculations.
For crypto specifically, every:
- Swap of one coin for another = a CGT event for the coin sold
- Spend of crypto on goods/services = a CGT event
- Earning of staking/airdrop rewards = ordinary income at the time received
- Gas/transaction fee = potentially part of cost base or expense
The ATO has clarified that crypto-to-crypto swaps are CGT events even if no AUD changed hands.
Why DIY gets this wrong
1. Cost base reconstruction
Most people don't keep clean records of cost base over the years. If you bought BTC in 2018, swapped some for ETH in 2020, used some to pay for a holiday in 2021, and sold the rest in 2025 — reconstructing the cost base is tedious and error-prone.
DIY filers typically:
- Use exchange-provided P&L statements that may not match ATO rules
- Forget to apply the correct cost-base method (FIFO is default for fungible assets; specific identification possible but only with contemporaneous records)
- Miss adjustments for crypto-to-crypto swaps
- Apply the 50% discount to ineligible assets (e.g., trader-status holdings)
2. Investor vs trader classification
The tax treatment differs dramatically:
| Classification | Tax treatment |
|---|---|
| Investor (default for casual traders) | CGT rules apply; 50% discount if held >12 months; losses offset capital gains only |
| Trader (business of trading) | Ordinary income rules; all gains/losses ordinary income/loss; no CGT discount; can offset against other income |
ATO looks at: frequency of trading, intention, scale, business-like systems, profit motive. Misclassifying yourself either way creates audit risk.
3. Crypto-specific gotchas
- DeFi protocols — providing liquidity, yield farming, lending all have specific (and contested) ATO treatments
- NFTs — generally collectables under CGT, but if you're trading them as a business, treated as trading stock
- Hard forks and airdrops — ordinary income at market value when received, then CGT applies on subsequent disposal
- Lost / stolen crypto — capital loss only if specific conditions met (proof of permanent loss)
- Wrapped tokens / bridges — generally CGT events though some argue otherwise
4. Share-specific complications
- Franking credits must be grossed up — the cash dividend + franking credit = your assessable amount
- Reinvested dividends (DRP) — each reinvestment creates a new parcel with its own cost base
- Off-market buybacks — special rules around capital vs dividend treatment
- Corporate actions (share splits, mergers, spin-offs) — each restructures the cost base differently
- Foreign-listed shares — foreign exchange gains/losses + foreign tax credits
ATO's data-matching means hidden gains are increasingly hard
The ATO receives data feeds from:
- All Australian share registries (Computershare, Link Market Services)
- Australian-domiciled exchanges (CoinSpot, Swyftx, Independent Reserve, BTC Markets, Kraken Australia)
- Foreign exchanges via OECD CRS (Common Reporting Standard) for transactions linked to Australian tax residents
- Some Australian banks regarding international wire transfers
If you omit a disposal that the ATO already has data for, you'll receive a "data-match" letter — often years after lodgement. Penalties and interest then apply.
This makes the "I won't bother reporting it" approach increasingly risky.
When DIY in myTax is still workable
A single CGT event with clean records:
- Held a single ASX-listed share parcel for >12 months
- Sold the entire parcel through one broker
- Cost base is the purchase contract note + brokerage; sale is the sale contract note minus brokerage
- 50% CGT discount applies straightforwardly
- No prior-year capital losses to track
This fits in myTax in 15 minutes.
For crypto with no more than 5–10 trades using a single Australian exchange that provides ATO-compatible reports, DIY is also viable — but stretch beyond that and the time/risk equation flips.
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*Disclaimer: This is general information only and does not constitute personal tax advice. Consult a registered tax agent for advice tailored to your specific situation. Always verify against the latest ATO guidelines at ato.gov.au.*
4 questions for crypto / share traders
Two or more "yes" → agent generally pays for itself in error reduction alone.
AI analysis on this page is general information only, not tax advice. Crypto tax in particular evolves quickly; consult a Registered Tax Agent for your specific holdings.