Whether you are taxed on your personal income in Belgium depends on your status. Evidently you will only pay taxes on your personal income to the Belgian State if you are on a Belgian payroll.. The amount of taxes you pay will depend on the level of your income and is calculated in percentages per installment. Specific rules are applicable for European civil servants, national seconded experts and trainees at the European institutions.
If you work as a self-employed person or an employee under the Belgian system, you will pay taxes. As an employee the State will directly deduct a fairly precisely calculated advance for the taxes and social security contributions from your wages. As a self-employed person however you can from your own free pay advances, although this is not mandatory. Employee and self-employed persons will need to fill in their annual tax form, which can be done on line viaTaxonWeb and will be partly prefilled by the State.
European civil servants
European civil servants are not required to pay Belgian personal income tax, since they fall under the Protocol on the Privileges and Immunities of the European Communities. As a result the salaries paid by European institutions are exempt from national income tax. Any EU official who receives an annual tax form should return it to the local tax office along with a document from the European Commission proving their status as an EU official.
National seconded experts
National detached experts continue to pay taxes in their home country and are not liable for Belgian income tax. Any EU official who receives an annual tax form should return it to the local tax office along with a document from the European Commission proving his status as an EU official.
Official trainees (stagiaires) at the European institutions are not covered by the Protocol on the privileges and immunities of the European Communities so they must complete and return their annual tax form. However, since their income will fall underneath the taxable limit, they will not pay any Belgian taxes on their income.