When do I have to declare crypto?

The short version: you declare your crypto income and capital gains from 2025 via the tax return you file in the spring of 2026. For the new capital gains regime (10%), this only applies to realizations from 1 January 2026 onward, to be filed in the spring of 2027.

Many Belgian crypto investors ask the same question: "When do I actually need to do something?" The panic is understandable. The rules have changed, the deadlines are vague in the media, and nobody wants to risk a fine.

This article explains it step by step.

🔍 Two different taxes, two different deadlines

To answer the deadline question properly, we first have to distinguish between two types of crypto income:

1. Miscellaneous income (diverse inkomsten) (speculative profits): This was the regime before 2026. If the tax authorities considered your crypto activity speculative, your profits were taxable at 33%. This applied to returns up to and including income year 2025.

2. Capital gains on digital assets (10%): New from 1 January 2026. A flat tax of 10% on realized capital gains, regardless of whether you are a "prudent person" (bonus pater familias) or an active trader.

The deadlines depend on which regime applies to you.

📅 Income year 2025: tax return in the spring of 2026

If you sold, exchanged, or converted crypto to fiat in 2025, these transactions still fall under the old regime. You declare this in the tax return for income year 2025.

When is that tax return due?

• Paper return: normally early June 2026 (the exact date is published each year by the FOD Financiën)
• Tax-on-Web (online): normally late June or early July 2026
• Via an accountant or proxy holder: until mid-October 2026

What do you need to fill in?

Speculative crypto profits are reported under "miscellaneous income (diverse inkomsten)" in the return (code 1440/2440). You calculate the difference between the sale price and the purchase price using the FIFO method. Losses are in principle not deductible from other income, but may be netted against profits of the same year.

🗓️ Income year 2026: tax return in the spring of 2027

If you sold, exchanged, or otherwise realized crypto after 1 January 2026, this falls under the new 10% capital gains tax.

Spring 2027, via the usual channels. The exact dates are not yet known, but the timing will be similar to previous years.

This already gives you some breathing room. You do not have to panic about a deadline that falls tomorrow. What you can do today is organize and keep track of your transaction data.

💰 What about staking income, airdrops, and DeFi rewards?

Crypto income that you receive (without selling anything) is taxable as movable income (roerende inkomsten) at 30% at the moment of receipt.

Think of:

• Staking rewards
• Airdrops
• DeFi yield (liquidity rewards, interest payments)
• Mining income

The market value at the moment of receipt is the taxable basis. Keeping track of when you received rewards and what the price was at that moment is therefore essential.

✅ When are you exempt? The "prudent person" principle

Under the old regime (up to and including 2025) there was an exemption for those who managed their crypto as a "prudent person" (bonus pater familias): a careful, long-term-oriented investor who does not trade speculatively. Anyone who met this standard paid no tax on capital gains.

From 2026 the 0% exemption disappears: capital gains from normal management are taxed at 10% (above the annual exemption of €10,000). The distinction between normal management and speculation remains crucial, however: normal management = 10%, speculation = 33%. Read more about the prudent person principle for 2025 and earlier.

⚠️ Common mistakes when filing

Forgetting transactions

Every swap, every sale, and every crypto-to-crypto exchange counts as a taxable moment. Anyone who only thinks of EUR exits potentially misses quite a few transactions.

Not applying the FIFO method

Belgium expects you to use the FIFO method (First In, First Out) to calculate your cost price. Anyone who does not keep accurate track of their purchases cannot do this correctly.

Mixing up income and capital gains

Staking rewards are income, taxable on receipt. Capital gains are only taxable on realization (sale/exchange). They may not be combined.

Waiting until the last moment

Requesting exchange exports and blockchain data takes time. Especially if you used multiple exchanges or wallets, you run the risk of falling behind in the spring of 2027.

🚀 Practical steps you can already take now

1. Export your transaction history at all the exchanges you use (Kraken, Binance, Coinbase, Bitvavo...) while all the data is still available. Some platforms limit historical exports after a while.
2. Document your wallet addresses and which wallets are yours. For the tax return, you have to be able to show that transfers between your own wallets are not taxable events.
3. Keep track of what you received in staking rewards or DeFi income, including the market value at the moment of receipt.
4. Use a tool that does the calculation for you. Cryptotax automatically imports your exchange data and on-chain transactions, applies FIFO, and generates a tax report that you or your accountant can use directly for the return.

🧾 Summary

The deadline for crypto taxes in Belgium is not tomorrow, but the preparation starts today. The sooner you have your data in order, the smoother the tax return goes.

Cryptotax automatically calculates your tax position based on your actual transaction data. Try it for free at cryptotax.be.

⚠️ Disclaimer: This article is purely informative and not individual tax advice. For concrete cases: consult a recognized Belgian tax specialist or request a ruling from the Ruling Commission (Dienst Voorafgaande Beslissingen).