The most consistent problem I encounter when helping Irish crypto investors get their tax affairs in order is not the tax law — it is the records. Or more accurately, the absence of them.
Someone contacts me in September wanting help with their crypto tax return. They have been trading since 2020. They have used five different exchanges, multiple hardware wallets, bridged assets between chains, earned staking rewards, received airdrops, and made hundreds of crypto-to-crypto swaps. They have no systematic records. Their memory of specific transactions is patchy. And they want to file an accurate return.
Reconstructing a clean transaction history from this position is possible — but it takes significant time and therefore cost, and the result is often less accurate than it would have been if records had been maintained from the start.
This article sets out the record-keeping system that prevents this problem. It is part of our comprehensive cryptocurrency tax guide series, and what follows is entirely practical.
What Irish Revenue Requires You to Record
For each crypto transaction, Revenue requires records sufficient to establish:
The date of the transaction. Whether it was an acquisition or disposal. The type of transaction (purchase, sale, swap, staking reward, mining, airdrop, gift, etc.). The cryptocurrency involved and the quantity. The value in euros at the date of the transaction. Any fees paid (acquisition or disposal costs). The exchange, wallet, or platform through which the transaction occurred.
These records must be retained for six years from the end of the tax year to which they relate. Revenue can request them in a compliance check.
Why Manual Records Fail
In theory, a spreadsheet with a row for every transaction could work. In practice, for anyone with moderate to high crypto activity, it fails for three reasons.
First, the volume of transactions is too high for manual entry. An investor staking on three protocols, trading on two exchanges, and using a hardware wallet for cold storage might generate 1,000+ entries in a year. Manual entry is not realistic.
Second, obtaining the historical euro prices for thousands of transactions at their exact timestamps requires access to price data that most people cannot easily access manually.
Third, applying the Irish FIFO identification rules across a complex portfolio with multiple acquisitions of the same asset at different times requires calculation logic that is extremely error-prone when done manually.
The Crypto Tax Software Solution
Crypto tax software tools are designed specifically for this problem. They connect to your exchanges and wallets via API, import your complete transaction history, obtain historical price data, apply jurisdiction-specific tax rules (including Irish CGT treatment), and produce a tax report showing your gains, losses, and income for each tax year.
The leading tools used by Irish investors and accountants include:
Koinly — strong exchange integration, solid Irish CGT support, generates output in a format suitable for an Irish accountant to review. Malone & Co. is listed on Koinly as an approved accountant for Irish clients.
CoinTracker — well-established, good DeFi support, clear gain/loss reports.
CryptoTaxCalculator — strong DeFi and on-chain transaction handling, useful for investors with complex multi-chain activity.
TokenTax — international focus, handles more complex structures including margin trading and derivatives.
None of these tools replaces an accountant. They produce a computed output that needs to be reviewed, verified, and in some cases corrected before being used to prepare a tax return. They do, however, reduce the cost and time of preparing that return by an order of magnitude compared to manual reconstruction.
Setting Up the System: Step by Step
Step 1: List every exchange, wallet, and platform you have ever used.
Create a complete inventory: every centralised exchange account (Coinbase, Binance, Kraken, Gemini, etc.), every hardware or software wallet (Ledger, Trezor, MetaMask, Phantom, etc.), every DeFi protocol you have interacted with, every blockchain your assets have touched.
Do not skip anything. A forgotten exchange account from 2018 with a small BTC balance may represent a disposal at a significant gain if those coins were later moved and sold.
Step 2: Export or connect your transaction history from every source.
Most exchanges allow full transaction history exports in CSV format. API connections (where available) are more reliable and capture more detail than manual CSV exports.
For on-chain wallets (Ethereum, Solana, etc.), the transaction history is publicly available on the blockchain and can be imported by providing the wallet address.
For DeFi protocols, on-chain data is generally captured automatically once wallet addresses are imported, though some protocols require specific integrations.
Step 3: Import everything into your chosen tax software.
Run the import across all sources. The software will attempt to match transfers between your own wallets (so they are not treated as disposals) and classify transaction types based on the data available.
Step 4: Review and correct the classified transactions.
No software is perfect. Common issues include:
Transfers between own wallets being misclassified as disposals. Staking rewards not being correctly identified as income. DeFi transactions being classified incorrectly due to complex smart contract interactions. Missing transactions where the API connection did not capture everything.
Review the classified transaction list, correct errors, and add any missing transactions manually. Pay particular attention to staking and DeFi rewards, which must be classified as income rather than capital gains. This review step is where professional involvement adds significant value — an accountant experienced in crypto tax will identify common classification errors that the software misses.
Step 5: Generate the tax report.
Once the transaction history is clean, generate the tax report for each relevant tax year. The report should show:
All disposals in the year with proceeds, cost, and gain/loss. Total net gains (or losses) for the year. All income events (staking, mining, airdrops) with euro values at receipt. Summary figures suitable for inclusion in the tax return.
The Ongoing Maintenance System
Having set up the historical record, maintaining it going forward is far simpler than initial reconstruction. The ongoing system:
At least quarterly (ideally monthly), sync your exchanges and wallets through the tax software. Review any new transactions for correct classification — particularly DeFi interactions. Record the euro values of any staking rewards or income events at the time of receipt if the software does not capture them automatically. After any significant disposal (a large sale or swap), calculate the estimated CGT liability and set aside cash for the tax payment.
Before You File: The Accountant Review
Even with good software, a professional review of the crypto tax report before it is incorporated into a return is valuable. The review should check:
That all acquisition sources have been captured (no missing exchange accounts or wallets). That the FIFO matching is being applied correctly. That income events are correctly separated from disposal events. That the payment dates for any CGT due are correct (December 15 for disposals in January–November), as detailed in our guide to reporting crypto on the Form 11.
The cost of this review is considerably less than the cost of an incorrect return that attracts a Revenue inquiry — particularly for investors with material crypto holdings.
Paddy Malone FCA AITI
Paddy is the principal of Malone & Co. Chartered Accountants in Dundalk. A Fellow of Chartered Accountants Ireland and a Chartered Tax Consultant with the Irish Tax Institute, he has been advising businesses across County Louth and the North-East for over 35 years.