Capital gains on shares: what the 2026 tax changes for your real estate company

What came into force

Since 1 January 2026, Belgium has taxed the gains that individuals realise on financial assets, including shares. The tax was first presented as a "solidarity contribution". Shares held through a company fall under a different regime, that of corporate income tax.

The general regime sets a rate of 10%, with an annual exemption of 10,000 EUR, indexed. The unused part can be carried forward at 1,000 EUR a year for up to five years, bringing the exemption to 15,000 EUR at most (30,000 EUR for a couple).

That general regime will not be yours, however. If you hold a real estate company, you almost certainly fall under a different one.

The regime that concerns you: substantial participation

As soon as you hold at least 20% of the rights in the company whose shares are transferred, you fall under the "substantial participation" regime.

One point is regularly misunderstood: the 20% threshold is assessed per individual shareholder, not at family level, at the moment of transfer. Two spouses holding 15% each do not reach it. Among siblings, a brother holding 25% falls under it while a sister holding 18% stays in the general regime.

Where ownership is split, as is common in family companies, it is the bare ownership that counts towards the threshold, not the usufruct.

For spouses married under a community property regime, jointly owned shares are split between them for this test: a joint holding of at least 40% is then needed for each of them to reach 20%.

The regime applies explicitly to holding, management and real estate holding companies, not only to operating businesses. In other words, it targets you directly.

The scale is progressive, after the first tranche is exempt:

• First 1,000,000 EUR exempt
• 1 to 2.5 million 1.25%
• 2.5 to 5 million 2.50%
• 5 to 10 million 5%
• above 10 million 10%

Watch the periodicity: the first-million exemption is available once every five years, not annually.

What stays protected: the 31 December 2025 snapshot

This is the most important part of this article, and the most neglected.

Only gains built up from 1 January 2026 are taxable. The value of your shares on 31 December 2025 becomes your tax acquisition value. Twenty or thirty years of gain accumulated before that date remain, in principle, out of the tax's reach, unless the tax authority demonstrates a speculative transaction or one outside the normal management of private wealth.

For listed shares, that value is the stock market price. For unlisted shares, the law sets the rule. The value used is, in principle, the highest of the following:

• the price of a transfer between independent parties, a capital increase or an incorporation that took place in 2025;
• the value resulting from a put-option formula set out in a contract and in force on 1 January 2026;
• a flat formula: equity plus four times EBITDA for the last financial year closed before 1 January 2026.

For a real estate company, this formula often gives a value well below reality. Its equity reflects buildings carried on the balance sheet at their historical, largely depreciated value, and four years of EBITDA weigh little against the value of a property portfolio. Yet the lower the starting value, the higher the taxable gain. The professional institutes themselves point out that the formula is purely a tax formula, not a valuation method.

By derogation, you can have this value established by a company auditor (réviseur d'entreprises) or a certified independent accountant, who may not be your usual adviser. This valuation must be established no later than 31 December 2027. Without it, the statutory rule applies.

Two traps worth knowing

Internal capital gains, taxed at 33%. If you transfer your shares to a company you control, alone or with your spouse or relatives up to the second degree (siblings included), the rate is neither the general one nor the progressive scale: it is 33%, with no exemption. Exit structures through a personal holding are the direct target.

Transfers outside the European Economic Area, taxed at 16.5%. Where the buyer is an entity established outside the EEA, a single rate of 16.5% applies, with the first-million exemption still available. The rule already existed, but the ownership threshold has been lowered from 25% to 20%.

What it actually changes for a seller

The share deal generally remains more advantageous than the asset deal. Selling the buildings triggers corporate tax on the gain (25%), then withholding tax to get the proceeds out of the company, and leaves an empty company to wind up. The new tax on shares, with a first million exempt and a scale starting at 1.25%, does not reverse that logic.

Valuation becomes an exercise at two dates. Today's value negotiates the price, using the buyer's method. The 31 December 2025 value establishes the taxable base, under the statutory rules set out above. These are two distinct exercises, governed by different rules.

Timing matters more than before. The first-million exemption applies per five-year period. For a family holding several companies, or siblings planning to sell at different moments, the order of operations is no longer neutral.

What to do now

• If your shares are unlisted, have their 31 December 2025 value established by a company auditor or a certified independent accountant, no later than 31 December 2027, rather than letting the flat formula apply.
• Check who holds what, individually and in bare ownership, to place each shareholder against the 20% threshold.
• If several transfers are envisaged, plan them across the five-year horizon of the exemption.