Losing, retaining and regaining Belgian citizenship
Subject to certain conditions, both adults and minors can lose Belgian citizenship.
There are two possibilities with respect to persons aged 18 and above: either no declaration stating their intention to retain Belgian citizenship (déclaration de conservation/behoudsverklaring) has been made or they have chosen to renounce their Belgian citizenship.
Minors may lose Belgian citizenship if a parent loses Belgian citizenship or if they are adopted by a foreigner.
Persons who have lost Belgian nationality in the past, can regain it under certain conditions.