Belgian income tax: How do I appeal?

How and where you appeal is explained on page 2 of your tax bill. You have to send a letter to the address in the middle of the page within six months after you receive the tax bill. That means the letter must arrive with the tax authorities within six months plus three working days from the date the tax assessment was sent out. That is the date on the tax bill. 

The tax authorities say they accept an appeal by fax or by email, but for the moment, I suggest you stick to pen and paper, scan it and send it by email and by ordinary mail. Preferably send the letter by registered mail so that you can prove the date. If you have waited until the last day, you can always bring it to the tax office and ask for a stamp confirming the date of receipt on a copy of the letter. Don't forget that, for the taxman, close of business is 16.00. If you find the door closed, you can try and send it by fax; you never know, if there is paper in the fax machine, the taxman may accept it.

Do I need an accountant or a lawyer to file an appeal?

No, you can do it yourself. 

Make sure that you have the correct address and that you mention all the relevant references on the top of the letter, just under your address (your N.N. or national number / social security number and the numéro d’article); you can find those in the box on page 1.  

Why not just attach a copy of the tax bill? 

Explain in detail why you don't agree. Maybe you forgot to mention a figure in the tax return, or the taxman himself overlooked a figure. Or all your expenses really are business expenses and not private entertainment. Or the taxman got it wrong, and a particular type of income is indeed not taxable. The most common mistake is that the taxman forgets to give an exemption for overseas income.

It is also advisable to ask for a meeting with the tax director. That may help you get your point across.

Finally, don't forget to sign the letter with your spouse or partner if it is also their tax bill.

And if I wait too long?

Six months seems like a long time, but they pass quickly. If you are too late, your request will be rejected, except in some cases. 

Sometimes the mistake is so obvious that it would be inequitable if the taxman didn't amend the tax bill. The tax authorities are allowed to reopen the tax file up to five years later if there are typos, miscalculations or glaring mistakes. Another reason for the taxman to reopen the file is when you have paid tax twice; in particular, if you paid tax in Belgium as well as in another country.

Conciliation

The tax authorities also offer some form of out-of-court dispute resolution. 

If the tax authorities do not agree with your tax return and they decide to amend it and send you a higher tax bill, you have to appeal it with a ‘réclamation’. 

If you think that the tax authorities will not modify their point of view, you can ask the Tax Conciliation Service to intervene. They will meet with you and try and work out an agreement that is acceptable to you and the tax office, and that agreement will be noted in the conciliation report.

As a result of this report, your appeal is settled along the lines of the agreement reached during conciliation.

More from our 2023 income tax guide

1. When do I need to file my Belgian income tax return?
2. Online or on paper?
3. Filing online
4. Understanding the paper tax return
5. Checklist: What documents do you need?
6. The return in detail
7. Belgian income tax: There's nowhere to hide
8. A guide to cross-border taxation
9. Belgian income tax returns for families
10. Help! Where to get assistance with your tax return
11. Understanding your Belgian income tax bill
12. How do I appeal?

• This guide was written by Marc Quaghebeur, an international tax lawyer at Cabinet DAVID. It is a general introduction based on current understanding of the law. It is not to be taken as a suitable alternative for individual advice. If you have a question, you can contact him by clicking on his name.