Ordinary adult nationality declaration

Five years and qualifying status

An applicant must be at least 18 and have five years of principal residence in Belgium based on lawful stay. Unlimited residence or establishment permission is required at filing; the preceding period normally requires permission to stay for more than three months. Residence and lawful stay must be continuous. Temporary absences of at most six months do not interrupt the statutory period if their total is no more than one fifth of the required period.

A2 national-language knowledge

Knowledge of one of the three national languages must meet CEFR A2 through accepted evidence. Proving social integration also proves language knowledge. A person certified by the competent Community authority as illiterate under the Code needs only A2 oral knowledge; this is a defined exception, not a general waiver.

Alternative social-integration evidence

Social integration can be shown by a qualifying upper-secondary-or-higher diploma or certificate; at least 400 hours of recognised vocational training; successful completion of the competent authority's integration or reception programme; or uninterrupted work throughout the preceding five years as an employee, appointed statutory civil servant or principally self-employed worker.

Separate economic-participation requirement

The ordinary route also requires at least 468 qualifying workdays in the preceding five years as an employee or statutory civil servant, or payment in Belgium of principally self-employed social contributions for at least six quarters in that period. The Code permits deduction of qualifying education or vocational-training duration completed within those five years from the required work duration; individual workday and training-credit calculations must be checked.

Belgium does not demand renunciation

Belgian authorities do not require an acquiring foreign national to renounce their existing nationality. Whether that nationality survives is governed by the other country's law; Belgium's allowance of multiple nationality does not guarantee retention elsewhere.

Declaration is not exceptional naturalisation

A declaration is filed with the civil registrar of the applicant's principal-residence municipality and is subject to official examination. Separately, naturalisation is a favour granted by the Chamber of Representatives, generally requiring exceptional merits and an explanation of why declaration is virtually impossible; a separate recognised-stateless-person provision exists.