Belgian Capital Gains on Securities (the 2026 "solidarity Contribution"): What M&A Teams Must Know

Who this is for: business owners selling significant shareholdings, acquirers, M&A lawyers, tax directors, family groups, private equity sponsors and in-house counsel. What it answers: scope, the control concept under Article 1:14 BCCA, timing, anti-abuse interaction, planning options and compliance steps for the new Belgian capital gains rules on securities taking effect on 1 January 2026, with particular attention to disposals to a company controlled by the seller or close family.

Belgium’s new capital gains contribution on financial assets (“securities”) takes effect on 1 January 2026 and is poised to reshape how private share disposals are structured and taxed. For the first time, many non-professional disposals of shares by individuals will be subject to a dedicated capital gains levy, and specific, stricter treatment is expected for so-called “internal” disposals, where the seller, alone or together with close family, controls the company that acquires the shares. This article explains the broad shape of the regime, the control concept it relies on, the timing of the taxable event, its interplay with the anti-abuse framework, and the practical steps M&A teams should take before and around the effective date.

Because several interpretative points remain unsettled and secondary legislation and administrative guidance are still being finalised, readers should treat this as general guidance and seek case-specific advice from a Belgian tax lawyer.

What are the new Belgian capital gains rules on securities?

The new rules introduce a dedicated contribution on capital gains realised by natural persons on financial assets (including shares) outside their professional activity. Historically, such gains were in many cases untaxed where they fell within the “normal management of private wealth”. From 2026, a capital gains levy applies to in-scope gains, subject to an exemption threshold and specific rules for substantial shareholdings. The exact rate, threshold and the treatment of historic value (“value as at the entry into force”) are fixed by the enacting legislation and accompanying guidance, and advisers should verify the current figures against the Federal Public Service Finance before relying on them.

A distinct and important feature concerns “internal” disposals. Where the seller disposes of shares to a company that the seller, or the seller together with close family, controls, the transaction may be treated less favourably than an ordinary disposal, because in economic terms the shares do not truly leave the family’s sphere of control. They are moved from a personally held position into a controlled holding structure. The policy rationale is to prevent the tax-efficient crystallisation of built-up value through transactions that lack a genuine third-party disposal, a pattern frequently seen in pre-sale reorganisations and estate planning.

The legislative basis and effective date are published through the official gazette (the Belgian Official Journal / Moniteur belge) and explained through guidance from the Federal Public Service Finance. Transactions with an effective date on or after 1 January 2026 fall within scope. The important conceptual shift is this: the question is no longer only whether a gain arises, but also whether the counterparty to the disposal is independent of the seller. Where it is not, the position can be materially less favourable than under the pre-2026 treatment.

Scope: who and what is caught under the new rules

The new capital gains contribution targets natural persons making non-professional disposals of financial assets, including shares. It is not aimed at traders or dealers acting in a professional capacity, those situations are governed by separate principles (professional income). Instead, the focus is the private individual realising a gain, with specific attention to the individual who sells shares to a company under their control.

Non-professional disposals

A “non-professional disposal” is, broadly, a sale of shares that falls outside the seller’s professional activity. These are precisely the transactions that, historically, could benefit from the private wealth management exemption. The new regime brings such gains into the tax net, and applies particular scrutiny where the acquirer is controlled by the seller or their close family. Typical fact patterns for internal disposals include:

• Sale to a newly incorporated holding company. An individual incorporates a holding company and sells its operating-company shares into it, realising a cash or receivable claim against value they already controlled.
• Family holding consolidation. Shares are transferred to a family holding company owned jointly by the seller, a spouse and children.
• Pre-sale reorganisation. Ahead of a genuine third-party sale, value is first moved into a controlled holding vehicle.

Exclusions and carve-outs

Disposals to a genuinely independent third party are not “internal”. The decisive factor is independence of the acquirer. The legislation also provides an exemption threshold for in-scope capital gains and specific rules for substantial participations, and it contemplates transitional measures (notably, protection of historic value accrued before the entry into force). Advisers should confirm the precise thresholds, the valuation reference for pre-2026 value, and any grandfathering provisions against the latest guidance from the Federal Public Service Finance before concluding that a carve-out or reduced charge applies. Because much of the perimeter is drawn by reference to control, the classification work must be done carefully and documented contemporaneously.

Control under Article 1:14 BCCA, de jure, de facto and joint control

The analysis of whether a disposal is “internal” borrows the concept of control from Article 1:14 of the Code of Companies and Associations (BCCA). Understanding this provision is a key analytical step for any M&A team assessing exposure. Article 1:14 distinguishes between control in law (de jure) and control in fact (de facto), and it also contemplates joint control.

De jure control, presumptions and examples

De jure control arises where a person holds legal powers that, in themselves, establish control. Under Article 1:14 BCCA, the principal situations include:

• Majority of voting rights. Holding, directly or indirectly, the majority of the voting rights attached to the company’s shares.
• Appointment powers. Having the right to appoint or dismiss the majority of the members of the administrative or management body.
• Control by agreement. Holding control under the company’s articles or by virtue of agreements entered into with the company.
• Shareholder-agreement majority. Disposing, under a shareholders’ agreement, of the majority of voting rights.

Where a seller holds the majority of voting rights in the acquiring company, the “internal” character of the disposal will ordinarily be established.

De facto control, indicators and evidence

De facto control is control that exists in practice without one of the formal de jure triggers. Article 1:14 BCCA presumes de facto control where a shareholder has exercised the majority of voting rights at the two preceding general meetings. More broadly, de facto control is a question of substance: who, in reality, directs the company’s policy? Relevant indicators include patterns of attendance and voting at general meetings, the degree of dispersion of the remaining shareholdings, influence over the composition of the board, and the practical ability to impose decisions. Because de facto control is assessed on the facts, contemporaneous evidence of genuine independence can be important.

Joint control among family, guidance

A particularly sensitive issue is joint control exercised by several persons acting together. For the purposes of identifying an internal disposal, the relevant notion is understood to focus on close family members acting in concert. This matters because it captures the classic estate-planning structure: parents and children jointly owning a family holding company into which the family’s operating shares are sold. Where the seller and close family together control the acquirer, the disposal may be internal even if no single individual holds a majority alone.

Advisers should rely on the precise wording of the legislation and any guidance published by the Federal Public Service Finance to determine how “close family” is delimited for this purpose, because the scope of that definition directly fixes the boundary of the stricter treatment.

As a practical workflow, deal teams should assess control in sequence: first test for de jure control; if absent, test for de facto control; and finally test whether control arises jointly among close family members. Each limb should be documented with the underlying share registers, voting records and shareholders’ agreements.

Timing, valuation and calculation of the gain

Once a transaction is in scope, the next questions are when the gain is taxed and how it is measured. Both carry practical traps for M&A teams.

Disposal date and valuation reference

The taxable event is generally fixed at the time of disposal. The gain is, in principle, the difference between the disposal consideration and the seller’s acquisition cost, subject to the statutory protection of value accrued before the regime’s entry into force, where applicable. Because internal transactions are between related parties, the authorities will scrutinise whether the consideration reflects genuine market value. An artificially inflated price used to extract value, or an artificially depressed price used to minimise the gain, both invite challenge. Independent, well-documented valuations prepared on an arm’s-length basis are therefore essential.

Where the valuation reference date differs from the signing or completion date, advisers should ensure the valuation is anchored to the correct date and supported by contemporaneous evidence.

Consideration types, cash, shares and contingent payments

Consideration structures affect both timing and quantum:

• Cash consideration. The cleanest case, the gain is measured against the cash price, tested for market value.
• Share or receivable consideration. Where the seller takes shares or a loan receivable in the acquirer, valuation of that non-cash consideration becomes central, and care is needed to avoid under- or over-statement.
• Contingent consideration and earn-outs. Deferred or performance-linked payments raise difficult questions about when the gain crystallises and how contingent amounts are valued at the disposal date. These should be modelled carefully, with the methodology documented so the position can be defended on audit.

Given the related-party context inherent in internal disposals, valuation is the area most likely to be tested. Robust, independent valuation evidence is the strongest protection against recharacterisation or an adjusted assessment.

Interaction with abnormal private wealth management and GAAR

The new capital gains rules do not operate in isolation. They sit alongside two pre-existing lines of defence available to the tax administration: the doctrine concerning abnormal management of private wealth and the general anti-abuse rule (GAAR). M&A teams must assess all three together, because a transaction may be challenged on more than one basis.

Abnormal private wealth management, test and overlap

Historically, gains on shares realised within the normal management of a person’s private wealth were, in many cases, not taxable; gains realised through transactions that went beyond normal management could be taxed as miscellaneous income. The abnormal management doctrine remains relevant and can overlap with the new regime: a transaction might still be attacked as abnormal management if it displays speculative or non-prudent characteristics. Advisers should therefore not assume that satisfying the new capital gains rules closes the matter.

GAAR, triggers and consequences

The Belgian general anti-abuse rule allows the administration to disregard, for tax purposes, a legal act or series of acts whose essential aim is to obtain a tax advantage contrary to the purpose of the relevant provision, where the taxpayer cannot demonstrate non-tax motives. If the administration successfully invokes the GAAR, it may recharacterise the transaction and tax it as if the abusive structure had not been interposed. In the context of internal disposals, GAAR risk is highest where the arrangement is engineered principally to crystallise or extract value tax-efficiently without genuine commercial substance.

Examples of risky structures

Structures that typically attract scrutiny include:

• Last-minute incorporations. An acquiring vehicle created shortly before the disposal with no operational function beyond holding the acquired shares.
• Circular value extraction. Sale proceeds funded indirectly by the target’s own reserves, so that value is returned to the seller with little real change.
• Cosmetic independence. Nominal third-party involvement introduced to defeat the control analysis while leaving effective control with the seller or close family.

The following risk matrix helps deal teams triage exposure under the new capital gains rules and the surrounding anti-abuse framework.

Any assessment of likely administration behaviour is editorial commentary; the practical effect in a specific case must be confirmed with a Belgian tax lawyer.

Practical planning options and unsafe strategies

Planning around the new Belgian capital gains rules should be defensive and substance-led, not aggressive. The aim is to understand and document the true nature of the transaction, not to manufacture artificial independence. The following guidance balances legitimate planning with the anti-abuse constraints described above.

Defensive planning checklist

• Test control early. Run the Article 1:14 BCCA analysis at the structuring stage, not at completion.
• Commission independent valuations. Support any consideration with arm’s-length, contemporaneous valuation evidence.
• Record commercial rationale. Document the genuine, non-tax reasons for the structure.
• Preserve governance records. Keep board minutes, voting records and shareholders’ agreements that evidence the actual control position.
• Review timing. Understand the consequences of transactions straddling 1 January 2026, including the treatment of historic value.

Structuring alternatives, pros and cons

None of these alternatives is a guaranteed route around the regime. Each carries its own tax profile and anti-abuse exposure, and the right choice depends entirely on the facts. The unifying principle for safe M&A tax planning in Belgium is substance: the chosen structure must reflect a genuine commercial and economic reality rather than a label designed to escape the control analysis.

Compliance, reporting and enforcement

Where a gain falls within the new rules, the taxpayer must report it in accordance with the applicable return obligations and be prepared to substantiate the reported position on audit. Compliance is not merely a filing exercise, the quality of contemporaneous evidence frequently determines the outcome of any later examination. Note that collection may, in some cases, operate partly through withholding by the relevant financial intermediary; advisers should confirm the applicable collection mechanics against current Federal Public Service Finance guidance.

Filing and evidence checklist

• Return disclosure. Report the gain accurately within the relevant tax return, with calculations retained.
• Valuation file. Keep the independent valuation report and its underlying assumptions, including any historic value as at entry into force.
• Control documentation. Retain share registers, voting records and appointment powers evidencing the control analysis.
• Commercial rationale. Preserve board minutes and correspondence showing the genuine purpose of the transaction.
• Transaction documents. Keep signed sale agreements showing the negotiated terms.

Appeals and litigation considerations

If the administration issues an adjusted assessment, the ordinary administrative objection and appeal routes apply, culminating where necessary in the courts of first instance and, on appeal, the courts of appeal. Interest and administrative tax increases may apply to additional amounts assessed. Criminal tax exposure is generally reserved for cases of serious fraud; the typical dispute concerns administrative assessment and recharacterisation rather than criminal liability. Strong contemporaneous documentation is the best foundation both for avoiding an assessment and, if one is issued, for defending it on appeal. Court precedents on sham transactions and recharacterisation illustrate the importance of genuine substance.

Practical worked examples

The following anonymised, illustrative examples show how the rules may apply in practice. The figures are purely illustrative and do not reflect any particular rate or threshold.

Example A, internal sale to a family holding company. An individual owns operating-company shares with an acquisition cost of EUR 200,000 and a market value of EUR 1,200,000. The individual incorporates a holding company owned jointly with their spouse and two children, and sells the shares to it for EUR 1,200,000. The seller and close family jointly control the acquirer under Article 1:14 BCCA. The disposal is internal, and the gain of EUR 1,000,000 is assessed under the specific treatment for internal disposals, subject to the statutory protection of any pre-2026 value.

Example B, sale to an independent buyer. The same individual instead sells the shares to an unrelated industrial acquirer for EUR 1,200,000 following arm’s-length negotiation. The acquirer is not controlled by the seller or close family, so the disposal is not internal. The gain is assessed under the general capital gains rules rather than the stricter internal-disposal treatment, though the transaction remains subject to the general anti-abuse framework if it were artificially constructed.

Comparison table: internal disposal vs ordinary capital gains vs abnormal management

Recommended checklist for M&A teams

1. Identify every disposal with an effective date on or after 1 January 2026.
2. Run the Article 1:14 BCCA control analysis, de jure, de facto and joint family control.
3. Confirm whether the acquirer is independent of the seller and close family.
4. Check the latest Federal Public Service Finance guidance on the rate, threshold, historic-value protection and close-family joint control.
5. Commission an independent, arm’s-length valuation anchored to the correct date.
6. Document the genuine commercial rationale for the structure.
7. Assess GAAR and abnormal-management exposure in parallel.
8. Model the tax outcome of any earn-out or contingent consideration.
9. Prepare the audit file: registers, minutes, agreements and valuation.
10. Obtain case-specific advice from a Belgian tax lawyer before closing.

Conclusion and next steps

Belgium’s new capital gains contribution on securities marks a significant change for private share disposals from 1 January 2026, with specific, stricter treatment for internal disposals to companies controlled by the seller or close family. It demands early, substance-focused planning from everyone involved in Belgian M&A. The decisive issues are whether the acquirer is controlled by the seller or close family under Article 1:14 BCCA, how the gain is valued at the disposal date, how pre-2026 value is protected, and whether the structure can withstand scrutiny under the GAAR and the abnormal management doctrine.

Because several interpretative points remain open and official guidance will shape outcomes, deal teams should document control, valuation and commercial rationale meticulously, and should obtain case-specific advice before closing. For tailored guidance on how these rules affect a particular transaction, contact us for bespoke advice.

Sources

1. Federal Public Service Finance (Belgium)
2. Belgian Official Journal / Moniteur belge (e-Justice portal)
3. Code of Companies and Associations (BCCA), consolidated text, including Article 1:14
4. OECD, Tax policy and anti-abuse guidance
5. Belgian Constitutional Court