Belgium's Proposed Capital Gains Tax On Financial Assets

Introduction

Despite its overall high tax burden, Belgium was one of the few countries worldwide that didn't have a general capital gains tax for individuals. The introductions of a capital gains tax by the Arizona coalition thus marks a significant shift in tax policy. Starting January 1, 2026, capital gains on shares & other financial assets will become subject to taxation under a newly proposed regime.

One important hurdle before its implementation on 1/1/2026 was the approval of the Council of State. In its opinion of last week, the Council would have raised some minor technical and procedural issues, but it should now be clear that the new tax does not raise fundamental constitutional objections.

The proposed legislative framework is complex and layered, and its implications extend far beyond retail investors. Business owners, company directors, and high-net-worth individuals will need to reassess their investment strategies, corporate structures, and estate planning arrangements in light of this development.

Scope of application

The main regime of which the press has reported tirelessly, is the broad-based 10% capital gains tax on financial assets. This default rule applies to the majority capital gains on transactions with financial assets. These include listed and unlisted shares, bonds, derivatives, investment funds, cryptocurrencies, currencies, and certain life insurance products. These gains will be taxed at a flat rate of 10%.

To soften the impact on smaller investors, a yearly exemption of 10,000 euros is provided, with the possibility to carry forward unused portions up to a maximum of 15,000 euros over five years. However, this exemption does not apply automatically when the tax is withheld at source; taxpayers must file a return to claim it. This gimmick- the outcome of a political squabble -has a limited impact and adds complexity to the regime.

The tax is triggered upon a transfer for consideration. The key criterion is whether the transfer results in a "realisation" of the gain, meaning that the asset leaves the taxpayer's estate in exchange for a higher value. Gifts, inheritances, marital contributions, and divisions of jointly held property are explicitly excluded. This distinction is particularly relevant in estate planning. E.g., the contribution of assets to a maatschap (partnership) may result in partial taxation, depending on the extent to which the contributing party retains ownership. Similarly, marriage benefits (i.e. survivorship clauses or attribution clauses) are not considered taxable events, even though they are legally classified as transfers for consideration.

In addition, the tax is also triggered if a taxpayer moves abroad. It does include an exit tax component. Belgian residents who move abroad will be taxed on the latent gains in their financial assets at the time of emigration. Relief is available for moves within the EU or to countries with qualifying tax treaties, but in other cases, the taxpayer can only defer payment of the tax due if they provide sufficient guarantees.

Valuation – an important 2025 deadline

Valuation rules are central to the implementation of the tax. Only gains realised after January 1, 2026 are taxable, and the value of the asset on December 31, 2025 serves as the benchmark.

• For listed assets, the closing price on that date applies.
• For unlisted assets, the law provides several valuation methods;
  • recent arm's length transactions;
  • contractual formulas (in Articles of Association or others) and;
  • EBITDA-based calculations.
  • valuation report prepared by an auditor or certified accountant, which can be rebutted by the tax authority.

In most circumstances, taxpayers will have to rely on that latter option, if they want to secure a somewhat realistic valuation as a basis for the capital gains tax. Taxpayers have until the end of 2025 to have that valuations per December 31, 2026 confirmed.

Collection & compliance

The tax will be collected either through withholding or self-reporting. Belgian financial institutions will be required to withhold the tax on gains from listed securities and insurance products, but not on crypto-assets, currencies, or transactions involving substantial shareholdings or internal gains. Taxpayers may opt out of withholding, but must then report all gains themselves. In addition, advisors involved in substantial or internal transactions may be subject to a mandatory reporting obligation, similar to the DAC6 regime for cross-border tax planning.

Special regimes: Internal gains & substantial shareholdings

Internal gains will be taxed at 33%. This regime already exists but is now explicitly recognised in the preparatory works. This regime is applicable when shares are sold to a company controlled by the seller or their close family. These transactions, often used in private wealth structuring or holding setups, will be taxed at a flat rate of 33 %. The rationale behind this high rate is to discourage tax-driven restructurings that allow shareholders to extract liquidity from companies without triggering dividend taxation. Notably, this regime applies only to sales, not to contributions in kind, which remain exempt under certain conditions.

A second regime embedded in the new capital gains tax targets substantial shareholdings. If the seller owns at least 20 percent of the company's capital at the time of the sale, the gain will be taxed progressively. The first one million euros of gain is exempt. Gains between one and 2.5 million euros are taxed at 1.25%, between 2.5 and 5 million euros at 2.5%, and between five and 10 million euros at 5%. Only gains exceeding ten million euros are taxed at the standard rate of 10%. However, if the buyer is a non-EU entity, the tax rate increases to 16.5% above the exempt threshold. This provision revives the previously existing rule on sales to non-EER entities, albeit in a more targeted form.

Conclusion

The new capital gains tax will introduces a complex and far-reaching set of rules that will affect a wide range of transactions. While the headline rate of ten percent may seem relatively modest, the interplay of exemptions, valuation rules, and special regimes creates a landscape that is quite complex and a lot of room for uncertainties.

Originally published 23 September 2025

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.