Establishing ‘parentage’

Where parents are married to each other, there is a presumption in law that the mother’s husband or wife is the father / co-parent of the child. When the couple are unmarried, this paternity or parentage needs to be formally established.

Under Belgian law:

  • if the mother is not married, the father / co-parent can declare their ‘parentage’ provided the mother agrees.

WORTH KNOWING: If a married man or woman declares parentage of a baby born to woman other than their wife, the wife will be informed.


How is a declaration of parentage made in Belgium?

Both parents need to sign a declaration of parentage (‘acte de reconaissance’ / ‘erkenningakte’).

When can the declaration of parentage be made?

The declaration of parentage can be made:

  • as of the sixth month of the pregnancy (based on the expected due date as indicated on a medical certificate from the gynaecologist);
  • at the time you register your baby at the commune (provided the mother is also present); or
  • any time after the birth (after the age of 12, the child also needs to give their agreement).

Special situations

Declaration of parentage in the case of stillbirth

Since a change of legislation as of 31 March 2019, in the case of stillbirth, it is now possible for an unmarried father / co-parent to declare parentage after the birth of their stillborn baby, provided the mother agrees.

Declaration of parentage of baby born to a women other than a person’s spouse

If a married man or woman declares parentage of a baby born to woman other than his/her wife, the wife will be informed.

Where is the declaration of parentage made and what documents are needed?

The declaration can be made at the commune in which you live, or at the commune in which you baby will be, or was born.

Both parents need to bring their:

  • identity cards;
  • birth certificates;
  • medical certificate stating the estimated due date, if making a prenatal declaration.

NOTE: procedures can vary slightly between communes, so it’s best to check in advance with your own commune.