In Sweden, a year you broke even on is still taxable.
Gains are taxed in full. Losses are deductible to seventy per cent. So a 10 000 kr gain against a 10 000 kr loss is not nil — it is 3 000 kr of capital income and 900 kr of tax on a year in which you made nothing at all. Every other country nets krona for krona, which is why a tool built for one of them understates this without ever looking wrong.
One per line:
date, buy|sell, asset, quantity, amount SEK, fee SEK — fee
optional. A swap is two lines, a sell and a buy, because in Sweden it is
both. Dates as YYYY-MM-DD.
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Netting the loss against the gain krona for krona, the way every other jurisdiction here does.
These figures are gross, as the form wants them. The seventy per cent quotation is applied by Skatteverket afterwards — a workpaper that had already quoted the loss would be wrong in the box it was copied into.
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Nine countries, and the widest spread is in Denmark
One average cost per asset across everything you hold, no schablonmetod, every swap a disposal — and thirty per cent of every loss simply not deductible.
The only place here where the usual bug runs the other way: a deemed acquisition cost of 20 per cent of the sale price — 40 after ten years — taken whenever it beats the real one, so an engine that just does proceeds minus cost overstates the tax. Work out the Finnish deduction →
Changes the question rather than the method: no capital gains tax at all, a deemed return on the value held at 00:00 on 1 January, and a counter-evidence rule whose «actual return» counts unrealised change, allows no costs and cannot go below zero. Work out the Dutch box 3 →
The widest spread of all: a gain is personal income in box 20 at up to 53 %, a loss is a deduction in box 58 worth about 26 %, and as a rule they do not offset each other at all. Work out the Danish boxes →
The mirror image on swaps: an exchange without a soulte is not a disposal at all, and the gain is a slice of what the whole portfolio cost rather than of what the coin cost. Work out the French formula →
Individual lots, tracked wallet by wallet since Rev. Proc. 2024-28. Losses net against gains in full. What your broker reports →
Pooled per asset under s.104 TCGA 1992, with same-day and next-30-day acquisitions matched first. Work out UK pooling →
Averaged like Sweden, but across all accounts and with superficial losses denied outright rather than quoted down. Work out Canadian ACB →
FIFO parcels with a twelve-month clock, and half the gain discounted — but only after losses are applied in full. Work out the Australian discount →
A harvested loss is worth 70% here
Sweden deducts only 70% of a crypto loss against other capital income, while the gain it is meant to cancel is taxed in full. Harvest 10,000 kr of losses against 10,000 kr of gains and you are left with 3,000 kr of capital income — the trade did not reach zero and no netting engine will tell you so. Work out what you are holding at a loss →
Questions
Why does a year I broke even on still produce tax?
Because the whole gain is taxed and only seventy per cent of the loss is deductible — «Hela vinsten beskattas men en förlust får endast dras av med 70 procent». A 10 000 kr gain against a 10 000 kr loss is 10 000 taxed against 7 000 deducted: 3 000 kr of capital income and 900 kr of tax on a year in which you made nothing. Every other country covered here nets krona for krona, which is why a tool built for one of them understates your Swedish tax without ever looking wrong.
Which cost basis method applies?
Genomsnittsmetoden, and only that. Every unit of the same cryptoasset you hold — across every exchange and every wallet — carries one averaged omkostnadsbelopp, recomputed each time you buy. There is no FIFO election, no per-wallet pool, and no matching rules in front of it.
Can I use schablonmetoden, the 20 per cent rule?
No, and this one catches careful people. For marketable shares you may use 20 per cent of the sale price as your cost basis when the real figure is worse, and the general K4 guidance says so. Skatteverket's cryptoasset page removes the option in as many words: «Schablonmetoden ... får inte användas när du redovisar kryptovaluta». A filer who read the general instructions and applied the 20 per cent rule to crypto has filed something the form does not permit.
Is swapping one crypto for another taxable?
Yes — it is a sale and a purchase at the same moment. Paying for goods or services with crypto is also a disposal. This is the exact opposite of France, where a swap without a soulte is not a taxable event at all, and it is why «the European answer» does not exist.
Should I write the quoted loss on the K4, or the real one?
The real one. The figures on the form are gross: the seventy per cent quotation is applied by Skatteverket after the K4, not by you. Section D totals reach punkt 7.5 for gains and punkt 8.4 for losses, and a workpaper that had already quoted the loss would be wrong in exactly the box it was copied into. This page shows both — what goes on the form, and what it ends up costing.
What does section D actually ask for?
One row per sale: beteckning, antal, försäljningspris, omkostnadsbelopp, and the resulting vinst or förlust. Sales are listed individually rather than netted. Försäljningspris is what you received AFTER the sale fee; purchase fees go the other way, into the omkostnadsbelopp.
What about a net loss year?
It becomes an underskott av kapital, and the tax reduction on that deficit is 30 per cent up to 100 000 kr and 21 per cent above — but that depends on your whole capital income, not on this ledger, so this page reports the deficit and does not price it.
What about staking, lending and mining?
Separate questions, and not capital gains on this holding. So is whether your activity is näringsverksamhet rather than capital, which moves everything. Neither is decided here.
Is anything uploaded?
No. This page computes entirely in your browser.
Run it on your real history
The full engine applies these same rules across every exchange export and public address you give it, with the source row behind each figure and the provision beside it. Free to see the answer.