Crypto capital gains calculator
Sold or swapped crypto with a Portuguese tax exposure? Check whether the 365-day exclusion applies to each disposal, what the 28% flat rate costs when it does not, and when a crypto-for-crypto swap is not taxed at all. Everything runs in your browser.
Enter an acquisition date, a disposal date and the two values to see what this disposal costs.
- NFTs and other non-fungible crypto-assets. art. 10.º n.º 21 CIRS puts them outside the definition this regime works on, and does not say where they land instead.
- Staking, mining, airdrop and validation rewards. art. 4.º-1(o) CIRS treats issuance, mining and consensus validation as a business activity (Category B); this tool computes Category G disposals only.
- Offsetting a loss against a gain, and the 5-year loss carryforward, for losses that are inside the regime — that is, on holdings of under 365 days.
- The counterparty side of art. 10.º n.º 24 CIRS. The relief is also withdrawn when the person or entity paying you is resident outside the qualifying states; this tool only asks where you are resident.
- Whether Portugal taxes a non-resident's crypto gain in the first place. That turns on source and treaty rules outside art. 10.º.
- The cost basis of anything you receive when a gain is excluded under art. 10.º n.º 22 CIRS — that article settles the tax, not the basis.
- Whether the charges on a crypto-for-crypto swap add to the cost that carries over under art. 10.º n.º 23 CIRS. Only the acquisition value is carried over here.
- Anything specific to assets acquired before 2023, when alínea k) came into force.
- Choosing to be taxed at your marginal rate instead of the flat 28% (englobamento).
- Paying the tax on a deemed disposal in instalments. art. 10.º-A n.º 3 CIRS does offer payment options — immediately, as each holding is realised, or in five equal annual instalments — when you lose Portuguese residency by moving to an EU/EEA state bound by administrative cooperation on tax. It is deliberately not applied here: n.º 3 offers those options for the tax on “o saldo positivo das diferenças referidas no número anterior”, and those differences are art. 10.º-A n.º 1's — share exchanges, mergers and demergers, and transfers of assets under art. 38.º CIRS. Nothing in art. 10.º-A reaches alínea k) of n.º 1 or art. 10.º n.º 25, and art. 43.º n.º 12 CIRS, which does reach n.º 25 by name, says nothing about how the tax is paid.
The 365-day exclusion, crypto-for-crypto rule, treatment of losses and deemed disposal on loss of Portuguese residence come from the current art. 10.º CIRS (n.os 20 to 25 after Decreto-Lei n.º 97/2026); the deemed-disposal valuation comes from art. 43.º n.º 12 and the 28% special rate from art. 72.º n.º 1 c). Sources were rechecked on 31 August 2026. Where those provisions do not settle a dependable result for a deemed disposal, the calculator now stops and requests professional review instead of applying Finkavo's interpretation.
Planning estimate only, and not tax advice. For ordinary disposals it applies one rule per line — excluded at 365 days or more, no tax on a qualifying crypto-for-crypto swap, 28% otherwise. For a positive deemed disposal on loss of Portuguese residence it deliberately gives no tax figure. Read the limitations above and have a certified accountant review anything you are about to file.
Join the waitlistFrequently asked questions
Is crypto tax-free in Portugal if I hold it for a year?
Not quite — the rule is counted in days, not months. art. 10.º n.º 22 CIRS excludes gains on crypto held for a period “igual ou superior a 365 dias”, so 365 days is enough but 364 is not, and twelve months on a calendar can be either. That is why this calculator asks for the two dates instead of a number of months: 1 March 2025 to 28 February 2026 reads as twelve months and is 364 days, which is taxable.
How is the gain worked out?
Sale value, less acquisition value, less documented charges on the purchase and the sale. A disposal that comes out negative is treated as zero — this calculator does not net a loss against a gain, and it does not carry a loss forward.
What if I am not a Portuguese tax resident?
art. 10.º n.º 22 CIRS attaches no residency condition to the 365-day exclusion, so this calculator applies it whether or not you are resident in Portugal. The one limit is art. 10.º n.º 24 CIRS, which withdraws the exclusion when you are resident outside the EU/EEA and outside any state with a tax treaty or an information-exchange agreement with Portugal. Separately, whether Portugal taxes your gain at all depends on source and treaty rules this tool does not model, so confirm that with an accountant.
Does it handle crypto-to-crypto swaps?
Yes. Under art. 10.º n.º 23 CIRS, when the consideration for a disposal is itself crypto and the 365-day exclusion does not already apply, there is no tax at that point and the crypto you receive takes on the acquisition value of the crypto you gave up. Select “Other crypto (a swap)” and the calculator reports the cost that carries over. The gain is deferred into the new holding, so keep that figure for when you eventually sell.
What about staking or mining rewards?
Not covered. This calculator computes capital gains on disposals only. art. 4.º-1(o) CIRS treats crypto issuance, mining and the validation of transactions as a business activity, which falls under Category B rather than the Category G rules modelled here.
I am leaving Portugal. Am I taxed on crypto I have not sold?
art. 10.º n.º 25 CIRS treats the loss of Portuguese tax residence as a disposal for the purposes of alínea k) of n.º 1 even though nothing was sold. art. 43.º n.º 12 measures a positive difference using market value on that date, acquisition value and acquisition-side charges. However, the current official text located by Finkavo does not settle every interaction needed to decide whether the 365-day exclusion applies to that deemed event. The calculator therefore shows the valuation difference but no tax estimate when it is positive; obtain professional advice or a binding ruling before filing.