What Is Tax-on-Web?
Tax-on-Web (accessible via MyMinfin.be) is the Belgian federal government's official platform for filing personal income tax returns online. It replaces the old paper form entirely for most residents and pre-fills much of your return automatically based on data from employers, banks, and government databases.
Filing online is not only faster — it's now the default expectation for the vast majority of Belgian taxpayers. Paper submissions are still possible but are being phased out for many categories of filers.
Who Needs to File?
Most Belgian residents — whether employed, self-employed, retired, or receiving certain benefits — are required to file an annual tax return. Exceptions exist for very straightforward situations where the government may propose a simplified return on your behalf, but it's always worth reviewing any pre-filled proposal.
What You'll Need Before You Start
- Your eID card and reader, or the itsme® app (for secure login)
- Your tax reference number (visible on any previous correspondence from the FPS Finance)
- Wage slips or a salary certificate (fiche 281.10) from your employer
- Bank details for any savings accounts or investments if applicable
- Receipts for deductible expenses (childcare, energy-saving works, charitable donations, etc.)
Step-by-Step: Filing Your Return on Tax-on-Web
- Go to MyMinfin.be and click "Tax-on-Web" under the personal tax section.
- Log in securely using your eID card reader or itsme® app. Choose the method that's most convenient for you.
- Review your pre-filled data. The system automatically populates fields from employer certificates, pension data, and bank information. Don't assume everything is correct — check each section carefully.
- Add any missing information. Deductible expenses such as mortgage interest, childcare costs, and donations to recognised charities must often be entered manually.
- Use the built-in simulation tool to see an estimate of your tax liability or refund before submitting.
- Submit your return. Once you're satisfied, click submit. You'll receive a confirmation number — save this.
Key Deadlines to Remember
| Submission Type | Typical Deadline |
|---|---|
| Online (Tax-on-Web) | Mid-July of the assessment year |
| Paper return | End of June (earlier) |
| Complex returns (via accountant) | Extended deadline in October |
Deadlines are confirmed each year by the FPS Finance. Always verify the current year's exact dates on MyMinfin.be.
Common Deductions Belgian Residents Can Claim
- Childcare costs: Certified daycare and after-school care expenses are partially deductible.
- Mortgage interest and capital repayments: Under certain conditions depending on your region and loan date.
- Charitable donations: Gifts of €40 or more to recognised organisations qualify.
- Home energy improvements: Insulation, solar panels, and heat pumps may be eligible for federal or regional tax benefits.
- Professional expenses: If you choose the actual expenses method instead of the flat-rate deduction.
What Happens After You Submit?
The FPS Finance processes your return and sends a tax assessment notice (aanslagbiljet / avertissement-extrait de rôle) — usually by late summer or autumn. This document confirms your final tax position: either a bill to pay or a refund to receive. Refunds are typically deposited directly into your bank account.
If you disagree with the assessment, you have the right to file an objection within a specified period, clearly stated on the notice.