Crypto is Box 3 wealth
For most people crypto is an investment in Box 3. You declare its value in euros on 1 January of the tax year, across all wallets and exchanges, including those abroad. It is taxed at the notional return for investments (6.00% for 2026) above your tax-free allowance, like shares.
Buying, selling and swapping during the year is not taxed separately. Only the 1 January value counts. Staking rewards and airdrops simply add to that value.
When it becomes Box 1 income
If your activities go beyond normal investing, for example mining on a large scale, trading with professional tools and very high frequency, or being paid in crypto for work, the income can fall in Box 1 as business profit or income from other work. Then real gains are taxed at income tax rates.
The Belastingdienst can see it
Since 1 January 2026, crypto service providers in the EU must report their customers' balances and transactions to tax authorities (DAC8). This does not change the tax, but undeclared holdings will be spotted. Correcting earlier years yourself leads to lower fines.
A bad crypto year
If your crypto lost value, your actual return may have been lower than the notional one, and you may be able to claim Box 3 tax back. Check with the Box 3 refund helper. Under the planned 2028 system, yearly value changes in crypto would be taxed directly; see the 2028 simulator.
Sources
This article is based on these official pages. If anything here differs from them, the official page is right.
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