For employees
Gross to net calculator 2026 (Belgium)
What do you keep in net pay? For employees, and for employers who want to agree a net salary. From gross to net pay for a full-time white-collar employee: personal social security contribution, work bonus, withholding tax using the 2026 key formula and the special social security contribution.
Net pay
| Breakdown | Amount |
|---|
Withholding tax is calculated with the key formula (annual basis: taxable pay × 12, flat-rate professional expenses, tax scale, reductions, divided by 12) and may differ by a few euros from the official scales. Your final personal income tax follows from your tax return.
Going part-time, for example 4/5? See with Working fewer hours how much net pay you lose, in steps of 4 hours.
Buying a home, alone or together? With How much can I borrow? you see roughly how much you can borrow on your net pay.
Explanation: gross to net in Belgium
Going from gross to net pay takes four steps in Belgium: the 13.07% personal social security contribution, the work bonus (a reduction for lower salaries), withholding tax using the 2026 key formula and the special social security contribution (BBSZ/CSSS). Employers who want to know the cost of the same gross salary use the employer cost calculator.
Frequently asked questions
How much of my gross salary do I keep?
That depends on your gross salary and family situation. First 13.07% personal social security is deducted (reduced by the work bonus for lower salaries), then withholding tax and the special social security contribution. Enter your gross salary in the calculator for an indication.
What is the work bonus?
The work bonus is a reduction of the personal social security contribution for employees on lower pay, which increases net pay. It disappears at higher gross salaries.
Is withholding tax my final tax?
No. Withholding tax is an advance payment of personal income tax. Your final tax follows from your personal income tax return.
What difference do dependent children make?
Dependent children lower the withholding tax and so increase net pay. The calculator takes the number of dependent children into account.
Note: indicative, not advice
This calculation is an indication based on general statutory rules and 2026 rates and is not tax, legal or payroll advice. Assumptions: full-time white-collar employee, resident of Belgium, no benefits in kind (e.g. company car), not married to a partner without income (marital quotient), no other reductions (e.g. single parent, disability). The work bonus differs for part-timers and blue-collar workers. Double holiday pay and the end-of-year bonus are taxed at separate, higher withholding rates and are not calculated here. Any changes to Annex III after 1 January 2026 (e.g. from the 2026 personal income tax reform) are not included. No rights can be derived from this result.
Something wrong or missing? Let us know
Sources & values used
| Item | Amount | Status |
|---|---|---|
| Personal social security contribution | 13.07% | RSZ/ONSS |
| Social work bonus part A (from 1-9-2026) | €127.54 up to €2,937.93; − 0.2739 × (S − 2,937.93); €0 from €3,403.62 | RSZ/ONSS |
| Social work bonus part B (from 1-9-2026) | €171.99 up to €2,300.62; − 0.2699 × (S − 2,300.62); €0 from €2,937.93 | RSZ/ONSS |
| Flat-rate professional expenses | 30%, max. €6,070 per year | Annex III 2026 |
| Tax scale (annual) | 26.75% up to €16,710 · 42.80% up to €29,500 · 48.15% up to €51,050 · 53.50% above | Annex III 2026 |
| Tax-free allowance reduction | €2,987.98 per year | Annex III 2026 |
| Dependent children (per year) | 1: €624 · 2: €1,656 · 3: €4,404 · 4: €7,620 · 5: €11,100 · 6: €14,592 · 7: €18,120 · 8: €21,996 · +€3,864 per additional child | Annex III 2026 |
| Tax work bonus | 33.14% of part A + 52.54% of part B | 2026: may have changed |
| BBSZ/CSSS | scale based on quarterly pay (individual assessment), max. €60.94 per month | RSZ/ONSS |
| Withholding tax via key formula | simplified (no rounding rules) | approximation |
- Social Security (socialsecurity.be) – Which contributions does an employer pay? (incl. 13.07% employee, structural reduction) (in Dutch)
- RSZ/ONSS – Administrative instructions: work bonus (amounts from 1 September 2026) (in Dutch)
- FPS Finance – Calculating withholding tax (key formula from 1 January 2026, Annex III Royal Decree/ITC 92, Belgian Official Gazette 29-12-2025) (in Dutch)
- RSZ/ONSS – Administrative instructions: special social security contribution (in Dutch)
Checked on 6 October 2026.