Belgium net salary calculator (Nettoloon, bruto-netto)
Belgium net salary calculator (Your Belgian net salary is gross minus RSZ social security and progressive income tax, after professional costs, the tax-free sum and the municipal surcharge.
Worked example · Netto / maand
You keep 67.1% of gross pay 32.9% goes to tax and contributions
With Bruto jaarloon of 45,000 EUR, this model computes Netto / maand of 2,518.07 EUR. See the full working.
✓ Verified against 2 self-test cases Updated for 2025 · sources checked 2026-08-02
How Nettoloon (net salary) in Belgium is calculated
Belgian payroll deducts RSZ/ONSS social security of 13.07% from gross, then allows a professional-costs deduction (a 30% forfait, capped) before tax.
Withholding tax is steeply progressive (25% to 50%), reduced by the tax-free sum, with a municipal surcharge of around 7% added on top. The calculator shows the contributions and taxable base. Estimate, not tax advice.
Worked example
ShowHide the full working: 1 input, 6 computed steps
| Inputs | |
|---|---|
| Bruto jaarloon | 45,000 EUR |
| Computed by the engine | |
| RSZ (13,07%) ✓ pinned | 5,881.50 EUR |
| Beroepskosten ✓ pinned | 5,930 EUR |
| Belastbaar ✓ pinned | 33,188.50 EUR |
| Belasting (incl. gemeente) | 8,901.68 EUR |
| Netto / jaar | 30,216.82 EUR |
| Netto / maand | 2,518.07 EUR |
Every computed row comes from the engine, run on the inputs above. Rows marked ✓ pinned are also fixed by a published self-test, so a change to the model that moved them would fail its own tests.
Frequently asked questions
What is the taxable base for 45,000 EUR in Belgium?
RSZ takes 5,881.50, the professional-costs forfait is capped at 5,930, leaving a taxable base of 33,188.50 EUR before the progressive scale.
What is the municipal surcharge?
Communes add a surcharge (opcentiemen) of typically 6-9% on the income tax, so the same salary nets slightly differently by town.
Why are Belgian taxes so high?
The withholding scale reaches 50% quickly, which is why the tax-free sum and professional-costs deduction matter so much.
Sources
- FOD Financiën Tax-Calc · checked 2026-08-02
- RSZ · checked 2026-08-02
Estimate. Not tax advice. The verification badge means the model reproduces the stated formula through 2 self-test cases; the sources support that the formula matches the rules.
Check the arithmetic yourself: how this calculator is verified — the formula behind every derived value, the 2 test cases the engine reproduces, and what the badge does and does not claim. Also available as machine-readable JSON.
Related calculators
Netherlands Nettoloon (net salary) · France Salaire net (net salary) · Luxembourg Salaire net (net salary) · Austria Nettogehalt (net salary) · Finland Nettopalkka (net salary)
Also for Belgium: Belgium Verkeersbelasting (road tax) · Belgium Indépendant (self-employed) · Belgium Vacances annuelles (annual leave)
All Belgium calculators · All calculators
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