Capital gains tax on crypto in Ireland, worked through

Capital gains tax on crypto in Ireland is worked out one disposal at a time: take what you received in euro, subtract what the coins cost you and any allowable fees, add up the year's gains, subtract losses, knock off the first €1,270 and charge 33% on what is left. Nothing is due on a coin you still hold, and nothing is due on a year where your net gains stay within the exemption, though you may still need to file.

This page is about the arithmetic. For the wider picture of what counts as a disposal, start with our crypto tax in Ireland overview; for filing dates and forms, see how to report and pay. All figures were checked on 5 October 2026, and Budget 2027 follows on 6 October 2026, so please re-check the rate and exemption on revenue.ie afterwards.

The formula, in the order you should do it

Revenue's CGT calculation page gives the formula as sale price minus purchase price minus allowable expenses. For crypto, the crypto manual (TDM 02-01-03) adds that the calculation is done "separately on each asset on a disposal-by-disposal basis". So there are really four steps.

First, list every disposal in the calendar year: sales for euro, swaps, purchases made with crypto, and gifts. Second, for each one, find the euro value received. Third, work out the cost of the coins disposed of and any allowable fees. Fourth, net the results together, apply losses, then the exemption, then the rate. The order matters because Revenue says the €1,270 is applied to "the first €1,270 of your gain or gains (after deducting losses)", and it can only reduce a gain. If your net gain is €960, only €960 of the exemption is used; the other €310 cannot be carried forward or given to anyone else.

Cost basis: what counts as "what you paid"

The cost basis is the euro amount you paid to acquire the coins you are now disposing of. If you bought 0.5 BTC for €10,000 on an exchange that charged a €60 fee, your cost is the €10,060 total, because the fee was an expense of acquiring it. Revenue's calculation page lists acquisition costs and disposal costs as allowable, and its crypto manual says fees are allowable too, though the manual's own examples leave them out to keep the numbers readable.

Three practical cautions. Network or "gas" fees on moving coins around between your own wallets are not obviously a cost of acquisition or disposal, so ask your adviser before deducting them. Coins you received for nothing, such as an airdrop, have no purchase price at all, and how to value them is not something the manual answers (see staking, airdrops and mining). And when you swap one coin for another, the euro value of what you received is your proceeds, and also the starting cost of the new coin. The manual asks for a "reasonable effort" at an appropriate exchange rate and accepts there is no single rate across exchanges, so pick a source, use it consistently and keep a note of it.

The pooling question: what we can and cannot say

If you bought the same coin at five prices and sell some, which purchase did you sell? Many countries have a rule. For crypto in Ireland, Revenue's manual states only that gains are computed disposal by disposal for each asset. It does not set out FIFO, average cost or share pooling, and we could not verify a published Revenue position on it. FIFO ("first in, first out") appears on Revenue's shares page, but that page is about shares.

Many tax-software tools apply FIFO by default, and many Irish accountants do too, but that is a professional practice rather than a rule Revenue has published for crypto. If you have a large number of purchases, ask your adviser what method they use, apply it consistently across the years, and keep a note of why.

The same caution applies to the four-week rule. Under section 581 of the Taxes Consolidation Act 1997, a disposal of shares or securities is matched with shares bought in the previous four weeks, and a loss on shares reacquired within four weeks is restricted. Revenue's crypto guidance does not say this applies to crypto, and several tax-software sites claim it does without citing a Revenue source. If you are thinking of selling at a loss and buying back straight away, take advice first rather than assume either way.

Three worked examples

The numbers below are illustrative and use round figures. They are not prices or predictions.

Scenario A: a straightforward sale. You bought 0.5 BTC for €10,000 plus a €60 fee. Later you sell it for €14,000 and pay a €90 selling fee. Cost is €10,060, proceeds net of the selling fee are €13,910, so the gain is €3,850. Deduct the €1,270 exemption and €2,580 is chargeable. At 33%, the CGT is €851.40. Because the sale happened in, say, March, the payment date would be 15 December.

Scenario B: a swap you might forget. You bought ETH for €2,000. Months later, with the ETH worth €3,500, you swap all of it for another token. Treating the swap as a disposal on general principles (the manual does not expressly address swaps), your proceeds are €3,500, your gain is €1,500, and the chargeable amount after the exemption is €230. CGT is €75.90. No euro ever reached your bank, which is exactly why swaps are missed. The new token starts with a cost of €3,500.

Scenario C: a gain and a loss in the same year. One disposal gives a gain of €4,000. A different coin you sold shows a loss of €1,500. Revenue's loss page says an allowable loss comes off chargeable gains of the same year. Net gain is €2,500, less the exemption of €1,270 leaves €1,230, and CGT is €405.90.

If instead you had made only a loss of €2,000 in one year and no gains, no tax would arise, but if you declare the loss it carries forward. Next year, with a gain of €5,000, you would deduct the €2,000 loss, leaving €3,000; after the exemption, €1,730 is chargeable and the tax is €570.90. Revenue says the unused loss has to be included in your returns, which is a reason to file even in quiet years.

Spouses and civil partners

Two points are directly sourced from Revenue's exemptions page. The €1,270 exemption is personal and cannot be transferred to a spouse or civil partner. And a gain on an asset transferred between spouses or civil partners is usually exempt from CGT, with some exceptions such as trading stock and certain non-resident transfers. Revenue's loss page also says special rules apply to spouses and civil partners. Whether and how this applies to a particular crypto holding is a point to confirm with an adviser.

Losses worth knowing about

Selling at a loss is a disposal like any other, and the loss is a real figure you can use. Lost coins, coins in a failed exchange and coins lost to a scam raise different questions: has there actually been a disposal, and can the loss be shown? We did not find a Revenue statement on negligible-value claims for crypto, so we make no claim about them here. Keep evidence of every such event and put the question to an adviser.

Common mistakes

• Ignoring swaps and small spending, which each count as a disposal.
• Using today's price rather than the price on the date of the transaction.
• Forgetting the fee on the buy side, which reduces the gain.
• Assuming the exemption carries over or can be shared with a spouse.
• Not filing a return in a year with a loss.
• Treating a wallet-to-wallet transfer as a sale. It is not a change of owner, but keep a record that proves the two wallets are yours.

For a quick estimate, use our crypto tax calculator, and for lawful ways to plan around the exemption and losses, read how to reduce crypto tax in Ireland. If you are about to sell, the practical side is in how to sell crypto in Ireland.

A note on valuing awkward cases

Most disputes about a crypto gain are really disputes about one number: the euro value at a particular moment. Revenue's manual accepts that no single exchange rate is authoritative, which gives you room, but also a duty to be consistent. Choose one source of historical prices for the whole year, such as the rate on the exchange where you traded, write down which source it is, and use it every time. If a coin was thinly traded or you swapped between two obscure tokens, say so in your notes and use the best evidence of value you can show, such as the euro price of one of the two legs.

Be careful with partial disposals. If you sell half a holding, the cost you claim is the cost of the half you sold, not the whole. And if the euro value of an asset changed between the order and the settlement, use the date the disposal took place, which is normally the date shown on your exchange statement. For the filing side, including which Revenue form applies to your situation and the dates to pay, see the Revenue CGT filing page and our own guide to reporting crypto tax.

When the maths is not the hard part

Plenty of people find the arithmetic easy and the paperwork hard. If you have used several exchanges, moved coins between wallets and swapped through decentralised services, reconstructing the cost basis can take longer than the calculation itself. The income-type receipts that arise from staking and similar activity follow different questions again, which we cover in our page on staking, airdrops and mining. Where there is real doubt, a qualified adviser is the cheaper route compared with an underpayment plus interest.