Crypto Tax in Portugal: the 365-Day Rule, 28% and What Else Counts

• Selling crypto that is not a security is a capital gain, Category G (CIRS art. 10.º n.º 1 k)). Gains and losses on crypto held for 365 days or more are excluded (art. 10.º n.º 22).
• Under 365 days, the positive balance of the year's gains and losses is taxed at 28% (art. 72.º n.º 1 c)), unless you opt to add it to your other income (n.º 13).
• Swapping crypto for crypto is not taxed when the 365-day rule does not already apply: the coins you receive keep the cost of the ones you gave up (art. 10.º n.º 23).
• Mining, issuing and validating transactions are business income, Category B (art. 4.º n.º 1 o)). Other remuneration from crypto operations is capital income, Category E (art. 5.º n.º 2 u)).
• Ceasing to be resident in Portugal counts as a disposal of your crypto for capital gains purposes (art. 10.º n.º 25).

Portugal taxes crypto, but not as one thing. A sale for euros is a capital gain, and whether it is taxed turns on how many days you held the coins. A swap for another coin is usually not taxed at all. Mining and validating are a business. Other payments for crypto operations are capital income. This guide takes each in turn, from the text of the IRS code and the AT's filling instructions, and says where our crypto capital gains calculator stops short of the law.

What you did decides the category

The code places crypto in three of its income categories. Category G covers capital gains (art. 9.º n.º 1 a)), and art. 10.º n.º 1 k) adds to it the onerous disposal of crypto-assets that are not securities. A crypto-asset, for the code, is any digital representation of value or rights that can be transferred or stored electronically using distributed ledger technology or similar (art. 10.º n.º 20). Unique, non-fungible crypto-assets are excluded from that definition (n.º 21), so NFTs sit outside the rules below.

The line between Category G and Category B is drawn by art. 10.º n.º 1 itself: a gain is a capital gain only when it is not business or professional income. The code sets no number of trades or turnover that makes you a business, so this guide does not invent one. If you trade crypto as an activity registered with the AT, start from the simplified regime guide. Staking is not named anywhere. The code puts transaction validation through consensus mechanisms in Category B and any other remuneration from crypto operations in Category E, and does not say which one a given staking reward is. That is a question for an accountant or a binding ruling, not for a calculator.

The 365-day rule is counted in days

Art. 10.º n.º 22 excludes the gains obtained, and also the losses incurred, on disposals of crypto-assets held for a period equal to or greater than 365 days. Read it literally, and three consequences follow. It is 365 days, not twelve months: 1 March 2025 to 28 February 2026 is twelve calendar months and only 364 days, so a sale on 28 February is taxable and a sale on 1 March 2026 is not. Exactly 365 days qualifies. And a loss on a long holding is excluded too, so it cannot be set against anything.

The Anexo G1 instructions head the quadro for these disposals as held for a period greater than or equal to 365 days, then describe it in the body as greater than 365 days. The statute says equal or greater, and the statute governs. If one of your sales lands on exactly day 365, keep the dates and be ready to show them.

Which coins you sold is not your choice. For crypto-assets, the ones disposed of are those acquired longest ago (art. 43.º n.º 8 g)). When your coins are held with more than one crypto-asset service provider, that rule applies separately at each one (art. 43.º n.º 9). So if you bought one coin on an exchange in 2024 and another on the same exchange in 2026 and sold one in 2026, the coin sold is the 2024 one, and it may well be outside the tax. The calculator asks for the acquisition date of each disposal; this is the rule for picking it.

Under 365 days: 28% on the year's balance

The gain on each disposal is the sale value less the acquisition value, less the expenses necessarily and actually incurred on the acquisition and on the sale (art. 51.º n.º 1 b)), such as exchange and network fees you can document. What is taxed is not each gain but the year's balance: art. 43.º n.º 1 nets the gains against the losses of the same year, and art. 72.º n.º 1 c) taxes the positive balance at 28%. That balance takes in the operations of alíneas b), c), e), f), g), h) and k) of art. 10.º n.º 1, so a crypto loss and a gain on shares land in the same calculation. A resident's loss does not count when the counterparty is subject to a regime referred to in art. 63.º-D n.º 1 or n.º 5 of the Lei Geral Tributária (art. 43.º n.º 7).

The calculator works one disposal at a time. A disposal at a loss under 365 days shows as a loss that is not offset, and the total adds up only the gains. If you have such a loss in the same year, the law taxes a smaller balance than the calculator's total: subtract it, or ask an accountant to check the netting across all your Category G operations.

If you are resident, you can instead opt to add the balance to your other income and be taxed at the general scale (art. 72.º n.º 13). The option is not for one line: art. 22.º n.º 5 makes it cover all your income of the same category, and the Anexo J instructions repeat that it brings in the other Category G income for which the option exists. A negative balance can only be carried forward to the next five years when you opt or are obliged to add it to your other income (art. 55.º n.º 1 d)). The obligation in art. 72.º n.º 14, for holdings of under 365 days when taxable income reaches the top bracket, is written for alínea b), shares and other securities, not for alínea k). The calculator does not model the option.

Crypto-for-crypto swaps, and when they are taxed after all

When the 365-day rule does not apply and you are paid in crypto-assets, art. 10.º n.º 23 says there is no taxation, and the coins you receive take the acquisition value of the coins you gave up. The gain is postponed, not forgiven: it is taxed when you eventually sell the new coins for money, measured from the old cost. Keep the original cost and date with the new holding, because that is the figure you will need.

Art. 10.º n.º 24 switches off both the 365-day exclusion and the swap rule when the person who earns the income, or the person who owes it, is not resident in an EU or EEA state or in a state with a double taxation convention or a tax-information-exchange agreement in force with Portugal. Its text points at «n.os 19 e 20», which is the numbering before Decreto-Lei n.º 97/2026 renumbered art. 10.º; those paragraphs are now n.os 22 and 23. The AT's annexes still cite the old numbers too. Anexo G has its own quadro 18B for these cases, whatever the holding period.

Leaving Portugal with crypto you have not sold

Art. 10.º n.º 25 treats the loss of Portuguese tax residence as an onerous disposal for the purposes of alínea k). Art. 43.º n.º 12 measures it: the positive difference between the market value on the date you stopped being resident and the acquisition value plus the charges inherent in the acquisition. A market value at or below cost gives no income under that formula, and the provision creates no loss to carry anywhere. Whether the 365-day exclusion reaches this deemed disposal is not stated by either provision, so when the difference is positive the calculator shows it and gives no tax figure. For when residence ends, see the tax residency guide. For business crypto, art. 31.º n.º 18 also treats ceasing activity and losing residence as a disposal.

Where it goes on the Modelo 3

Each crypto quadro asks for the realisation and acquisition values and dates, the deductible expenses and the counterparty's country; the Anexo G and G1 quadros also ask for the service provider that held the coins. The opt-in to add the gains to your other income is field 01 of Anexo G quadro 15, or of Anexo J quadro 9.4B. Anexo G and Anexo J both have a quadro for crypto held under 365 days, and the instructions do not define when a crypto gain counts as obtained abroad, so confirm the annex with the form you file. The rest of the return is in the IRS 2026 filing guide, and foreign income in general in the Anexo J guide.

What the calculator does not do

• Net a loss under 365 days against a gain, or carry it forward. The law does both, in the conditions above.
• Add the gains to your other income. That option exists (art. 72.º n.º 13) and is not modelled.
• Category B and Category E crypto income. It computes Category G disposals only.
• NFTs, which the code takes out of the definition (art. 10.º n.º 21).
• The counterparty side of art. 10.º n.º 24. It asks only where you are resident.
• A tax figure on a positive deemed disposal when you leave Portugal.

Checklist

• For each provider, list every purchase and disposal with its date, euro value and fees.
• Match each disposal to the oldest coins held at that provider, and count the days held.
• Separate sales for money from swaps for other crypto.
• Total the year's gains and losses under 365 days; the positive balance is what 28% applies to.
• Put income from mining, validating or crypto remuneration aside: it is not Category G.
• If you left Portugal this year, value your holdings on the date residence ended.