Capital gains tax in 10 questions

In principle, a tax on capital gains from financial assets has been introduced in Belgium since 1 January 2026, even though the relevant legislation has not yet been passed. Below, we summarise the most important points for you, subject to any possible amendments.

1. Who does this new tax apply to?

The capital gains tax on financial assets applies to:

  • Private individuals subject to personal income tax in Belgium
  • Non-profit organisations subject to Belgian legal entities tax (such as non-profit associations and foundations), with the exception of organisations that are entitled to receive tax-deductible donations.

Do you have a company? This new tax does not apply to you: any capital gains you realise are already subject to corporate income tax.

2. Will all my investments be taxed from 2026?

No. Only realised capital gains on your investments are taxable. In other words, the profit you make, for example, when selling shares or bonds. In many cases, an exemption from this tax is possible.

The new tax does not apply to all types of investments. A summary table below explains in more detail.

The capital gains tax applies to:

  • Shares, whether listed or unlisted, held individually or within an investment fund (UCITS)1
  • Bonds
  • Investments in funds and ETFs (trackers)1
  • Derivative products (options, futures, swaps, etc.)
  • Financial life insurance products (branches 21, 23 and 262)
  • Physical gold3
  • Currencies and cryptocurrencies3

The following remain outside the scope of the tax:

  • Pension savings
  • Long-term savings
  • Group insurance schemes
  • Physical precious metals other than gold (silver, platinum, palladium, etc.)3
  • Dividends and interest on which you already pay 30% withholding tax

1 In addition to the new capital gains tax, the Reynders tax on bond funds remains in force.
The 2 taxes are applied separately:

  • 30% withholding tax on income from the bond portion (Reynders tax)
  • 10% tax on the balance of capital gains upon transfer (new capital gains tax)

In practice, the capital gains tax will rarely apply to branch 26, as withholding tax generally already applies.

Not offered by BNP Paribas Fortis.

3. How is the taxable value calculated?

The tax is not levied on your total selling price, but on the difference between the gross purchase price and the gross selling price (i.e. before costs and taxes).

Example:

  • In 2026, you buy 10 shares at €100 each.
  • In 2028, you sell these 10 shares at €130 each.

Your total selling price of 10 × €130 = €1,300 is not taxable. It is your gain of 10 × (€130 − €100) = €300 that is taxed.

In the case of staggered purchases - for example, if you bought the same share in company X at different times, the FIFO principle (First In, First Out) applies when selling. The tax authorities consider the shares you purchased first to be the ones you sell first.

Example:

  • In 2026, you buy 20 shares at €100 each.
  • In 2027, you buy a further 20 shares at €120 each.
  • In 2029, you sell 30 of these shares at €150 each.

It is not your total selling price of 30 × €150 = €4,500 that is taxed, but your gain of €1,300. The tax is calculated as follows:

  • 20 × (€150 − €100) = €1,000
  • 10 × (€150 − €120) = €300

4. How much is the tax and does it apply from the first euro?

The basic rate is 10%. The first €10,000 per taxpayer per year is exempt from tax (€20,000 for married couples under the community of property regime).

This amount will probably be indexed each year.

Example:

  • In 2026, you buy 10 shares at €100 each.
  • In 2028, you sell these 10 shares at €130 each.

The capital gains tax amounts to 10% on your gain of 10 × (€130 − €100) = €300, i.e. €30. You can use your available exemption to recover these €30 via your tax return for that income year.

5. How is the tax collected?

Legal entities must always declare their realised capital gains themselves via their annual legal entities tax return.

Private individuals can choose how the capital gains tax is collected:

  • Withholding at source (‘opt-in’)

By default, the new tax is automatically withheld at source (with the exception of capital gains realised on foreign securities accounts or on the sale of cryptocurrencies or physical gold).

Withholding at source means that, in the event of a sale, your bank immediately withholds the 10% tax on your gains and transfers it to the tax authorities. In this case, you do not have to declare your capital gains yourself in your tax return, unless you wish to make use of your exemption and/or offset capital losses.

Please note that you can only claim your exemption or offset capital losses via your tax return for the following tax assessment year. It will therefore take 1.5 to 2 years before the amount withheld is effectively refunded to you.

Transitional regime

Do you prefer withholding at source? Your bank can only withhold the 10% capital gains tax after the final law has been published. However, you may choose that, in the event of a sale between 1 January 2026 and the date of publication, we already withhold a provisional amount corresponding to this 10% tax. We will transfer this amount to the tax authorities once the law is published. In that case, you do not need to declare these capital gains yourself in your tax return for the 2026 income year (tax assessment year 2027).

  • Personal declaration (‘opt-out’)

You may also choose to declare your realised capital gains yourself as from the 2026 income year (tax assessment year 2027) via your tax return. Your bank will not withhold 10% of your gains, but it is nevertheless required to provide the tax authorities with a tax certificate containing all relevant data relating to the sale of the investments concerned for verification purposes.

You will be able to inform us of your choice to opt in or opt out at a later stage. For financial life insurance products, this choice depends on the insurer.

6. What do I have to declare myself?

Whether you choose to opt in or opt out, you must always make a personal declaration yourself in the following cases:

  • If you have realised capital gains on foreign securities accounts or on the sale of cryptocurrencies or physical gold
  • If you wish to claim an exemption from the tax
  • If you wish to offset realised capital losses

7. How is the taxable capital gain calculated for investments made before 1 January 2026?

Only capital gains realised as from 1 January 2026 are taxable. It was therefore important to determine the value of your investments accurately as at 31 December 2025. In accordance with the regulations, your bank therefore took a ‘snapshot’ of your portfolio on that date. By default, the taxable capital gain is the difference between the value of your investment at the time of this snapshot and the higher price you receive when you sell it as from 1 January 2026.

Example:

  • In 2023, you buy 10 shares at €80 each.
  • At the time of the snapshot on 31 December 2025, these 10 shares are worth €100 each.
  • In 2028, you sell the 10 shares at €130 each.

It is not your total gain of 10 × (€130 − €80) = €500 that will be taxed, but your gain since the time of the snapshot, i.e. 10 × (€130 − €100) = €300.

8. What happens if the ‘snapshot value’ is lower than my purchase price?

If, as at 31 December 2025, the value of your investment was lower than its purchase price, the taxable capital gain calculated on the basis of the snapshot will be higher than your actual gain.

Example:

  • In 2023, you buy 10 shares at €100 each.
  • At the time of the snapshot on 31 December 2025, these 10 shares are worth €80 each.
  • In 2028, you sell your 10 shares at €130 each.

Your capital gain calculated on the basis of the snapshot amounts to 10 × (€130 − €80) = €500, while your actual gain is 10 × (€130 − €100) = €300.

You may deduct this capital loss via your tax return, subject to certain conditions.

For staggered purchases, the weighted average purchase price of the investments you held on 31 December 2025 is used.

Example:

  • In 2024, you buy 20 shares at €90 each.
  • In 2025, you buy a further 20 shares at €100 each.
  • At the time of the snapshot on 31 December 2025, these 40 shares are worth €80 each.
  • In 2027, you sell 30 of these shares at €110 each.

Your weighted average purchase price for the 40 shares is ((20 × €90) + (20 × €100)) / 40 = €95. Based on the snapshot value, your capital gain amounts to 30 × (€110 − €80) = €900, but based on your weighted average purchase price, it amounts to 30 × (€110 − €95) = €450.

Please note

As from 2031, the snapshot value will always be used as the basis, even if it is lower than your original purchase price.

9. Is the exemption of up to €10,000 automatic?

No. You must always claim the exemption yourself via your tax return, even if you opt for withholding at source (opt-in). Your realised capital gains can be taken into account in order to benefit from the exempt tranche of €10,000.

If you do not use your annual exemption, or do not use it in full, you may carry forward €1,000 to subsequent years. You can do this for up to 5 consecutive years. In this way, you can build up an exemption of up to €15,000 if you have not used it during the previous 5 years (€30,000 for married couples under the community of property regime).

Any exemption carried forward to the following year is used first if you make use of your exemption in that year.

Example:

Year Available exemption Capital gain realised Exemption used Taxable capital gain Exemption carried 
2026 €10,000 €0 €0 €0 €1,000
2027 €11,000 €3,000 €3,000 €0 €0
2028 €10,000 €20,000 €10,000 €10,000 €0
2029 €10,000 €0 €0 €0 €1,000
2030 €11,000 €12,000 €11,000 €1,000 €0
2031 €10,000 €0 €0 €0 €1,000

10. Are capital losses tax-deductible?

That depends on the situation:

  1. Capital losses realised on a sale before 1 January 2026 are not deductible (likewise, gains realised on a sale before 2026 are not taxable). You therefore cannot offset them via your tax return.
  2. If you sell an investment at a loss as from 1 January 2026, you may deduct that capital loss from your realised capital gains, but only in the same year. You cannot carry these losses forward to subsequent years.
  3. You may also temporarily deduct capital losses resulting from the difference between your purchase price and the snapshot value of your investment. This is only possible if the sale takes place within 5 years following the snapshot, i.e. up to and including 31 December 2030.