Are you working in Belgium even though you don’t live here permanently? Or do you officially live abroad, while you earn an income in Belgium? In that case, you should file a tax return for non-residents. The same applies to companies with their registered office abroad.
As long as you receive income from Belgium, you must file a tax return for non-residents. If this is your first time, you should start by registering online. You will then receive a paper return by post in the course of the second semester of the tax year. You can also choose to submit the declaration online over the MyMinfin platform. For this, you need an electronic identity card, a card reader and your pin code. You will automatically receive the second tax return by post.
Good to know: any change of address abroad or change in your family situation should be reported to the FPS Finance as soon as possible.
If you live in Belgium officially, but work in another country (or vice versa), you run the risk of being taxed twice. Once in Belgium, because the Belgian authorities charge tax on worldwide income, and once in the country where you work, because most countries tax the income earned on their territory, regardless of whether you actually live there.
Fortunately, most countries have concluded bilateral tax treaties, which prevent double taxation.