Belgian Supreme Court reshapes the social security treatment of RSUs

On 29 June 2026, the Belgian Supreme Court (Cour de cassation / Hof van cassatie, S.24.0021.N) issued an important judgment on Restricted Stock Units (“RSUs”) granted by a foreign parent company to employees of Belgian subsidiaries. The Court held that benefits intended to retain employees, maintain their commitment or encourage diligent performance can constitute remuneration for work. For multinational groups operating RSU plans in Belgium, this may materially increase the cost of these awards.

1. What happened?

The case concerned RSUs granted by a foreign parent company to selected employees of Belgian subsidiaries under a global equity incentive plan.

In 2023, the Antwerp Labour Court had ruled that the RSUs at issue were not subject to Belgian social security contributions. Several elements supported that conclusion:

• the RSUs were granted by the foreign parent company;
• the Belgian subsidiaries did not finance the awards;
• the Belgian subsidiaries had no contractual obligation to grant them;
• the contractual relationship concerning the RSUs existed directly between the parent company and the employees; and
• the plan was designed, in particular, to retain selected employees within the group.

The Belgian National Social Security Office (“NSSO”) challenged that decision before the Supreme Court.

2. What did the Supreme Court decide?

The Supreme Court quashed the Antwerp Labour Court’s judgment and referred the case to the Brussels Labour Court for reconsideration. The key point of the judgment concerns the concept of remuneration as consideration for work. 

According to the Supreme Court, benefits granted by a foreign parent company in order to:

• retain employees;
• encourage their continued commitment; or
• ensure diligent performance,

can themselves constitute benefits granted as consideration for work and therefore remuneration for employment-law purposes.

This is particularly important for RSU plans.

The retention purpose of an award had previously been relied upon as an argument that the RSUs resulted from an autonomous incentive policy of the foreign parent company rather than from the Belgian employment relationship.

The Supreme Court’s judgment significantly weakens that argument: the fact that an award is intended to retain and motivate an employee may itself establish the required connection with the work performed.

Importantly, the Supreme Court did not rule that every RSU granted by a foreign parent company automatically attracts Belgian social security contributions. The qualification will continue to depend on the legal and factual characteristics of the relevant plan.

Nevertheless, the principle established by the Court is broad and is likely to have important practical consequences.

3. What is the potential cost?

Where RSUs qualify as remuneration for Belgian social security purposes, ordinary Belgian social security contributions may become due.

In general terms, this means approximately:

• 13.07% employee social security contributions; and
• around 25% employer social security contributions, depending on the employer and the contributions applicable in the specific circumstances.

If the RSUs are subject to a non-transferability clause of at least two years from the date of grant, the social security contribution is in principle calculated on the basis of 100/120ths of the market value.

The overall impact may therefore be substantial, particularly for multinational groups using RSUs as an important component of executive or employee compensation.

Qualification as remuneration may also have consequences beyond social security. Depending on the circumstances and the applicable employment-law rules, RSUs could potentially affect certain remuneration-related entitlements or liabilities, such as holiday pay or termination payments.

4. What should multinational employers do now?

International groups with Belgian employees participating in RSU or similar equity incentive plans should review their arrangements in light of the judgment.

Particular attention should be paid to:

• the purpose described in the plan and award documentation;
• vesting and continued-employment conditions;
• forfeiture provisions when employment terminates;
• the involvement of the Belgian employer in selecting or recommending beneficiaries;
• communications made to employees concerning the awards;
• which entity grants and finances the RSUs; and
• the Belgian payroll and social security treatment applied to current and previous awards.

Existing exposure for periods that remain open under the applicable limitation rules should also be assessed where relevant.

5. Key takeaway

For multinational groups, the judgment materially changes the risk analysis surrounding RSUs granted to Belgian employees.

In particular, an award’s retention or incentive purpose can no longer safely be relied upon as an argument that the benefit falls outside remuneration. On the contrary, that purpose may support the conclusion that the award constitutes consideration for work.

Groups operating RSU plans in Belgium should therefore review both their current arrangements and their historical social security treatment.

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