Article 8, § 1, 2°, b), of the Belgian Nationality Code grants Belgian nationality to a child born abroad of a Belgian parent, provided that parent files, within a five-year deadline from the birth, a declaration claiming that nationality for the child. Once that five-year deadline has passed, the law in principle offers no way to catch up. Recent case law, and now the Constitutional Court, temper that strictness.
The principle set out in Article 8 of the Nationality Code
A child born abroad of a Belgian parent does not always acquire Belgian nationality on that basis alone. Where the Belgian parent was themselves born abroad, attribution requires a declaration claiming Belgian nationality for the child. No specific form is imposed, however. What matters is the Belgian parent’s will to pass on their nationality to the child. A manifestation of that will, in whatever form, can amount to a declaration of attribution. The real constraint is time. That will must be expressed within the five-year deadline, before the child’s fifth birthday.
A reading more attentive to the child’s situation
The rigidity of the text is increasingly contested. Case law accepts that force majeure may justify extending the period where the parent was prevented from acting. The Brussels Family Court held that a consular blockage and the need to complete prior formalities could amount to such force majeure, and granted an additional six months to allow the parent to declare the child. Other decisions rely on the best interests of the child to grant an extension.
The Constitutional Court went further. In its Judgment No. 51/2026 of 23 April 2026, it held that a child whose Belgian parent died during the five-year deadline, without having been able to file the declaration, cannot be deprived of Belgian nationality on that ground alone (our analysis of that judgment). The judgment establishes, in principle, a right for the child to have their situation examined where the declaration could not be made in time.
The questions pending before the Constitutional Court
The French-speaking Court of First Instance of Brussels has referred new preliminary questions to the Constitutional Court, published in the Belgian Official Gazette on 28 January 2026. They bear directly on Article 8, § 1, 2°, b), and challenge the absolute nature of the deadline, in particular for children who have reached majority and within a sibling group where one child was able to obtain attribution or an extension.
The first question reads as follows.
"Does Article 8, § 1, 2°, b), of the Belgian Nationality Code infringe Articles 10, 11 and 22bis of the Constitution, read alone or in conjunction with Articles 8 and 14 of the European Convention on Human Rights and Article 3 of the Convention on the Rights of the Child, in that it creates a difference in treatment between children of the same sibling group, since a Belgian parent may no longer be entitled to make the declaration attributing Belgian nationality for a still-minor child aged over five, while retaining that possibility for children under five or for future children, whereas the genuine link with Belgium is assessed in the person of the Belgian parent and therefore does not vary from one child to another?"
The second question is the following.
"Does Article 8, § 1, 2°, b), of the Belgian Nationality Code infringe Article 22bis of the Constitution, read alone or in conjunction with Article 8 of the European Convention on Human Rights and Article 3 of the Convention on the Rights of the Child, in that it does not provide, in the child’s best interests, a review procedure allowing the Belgian parent to obtain a new period within which to make the declaration attributing nationality for their minor child where they can prove a genuine connecting link with Belgium?"
The differences in treatment identified by the court are serious. The same Belgian parent may still declare a child under five or a child to come, but no longer a minor child aged over five, even though the link with Belgium is assessed in the parent and does not vary from one child to another.
What the Court’s answer could change
A favourable answer would widen access to Belgian nationality for children born abroad of Belgian parents who were themselves born abroad. In the meantime, options already exist where the declaration was not filed within the five-year deadline of Article 8, § 1, 2°, b), of the Nationality Code, whether through force majeure, the best interests of the child, or the lessons of the judgment of 23 April 2026. Each situation calls for an individual assessment.
Céline Verbrouck
Attorney at the Brussels Bar
Specialised in immigration law, nationality law and international family law
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