Belgium Tax Changes 2027: What the Income Tax Reform Changes
The reform law of 15 July 2026 is adopted. For income year 2027 it raises the tax-free amount and child supplements, cuts the marital quotient, and adds a 10% entrepreneur deduction and a 33% rate for working pensioners.
Main change for 2027
On wages of employees who also receive a retirement or survivor's pension, from 1 January 2027
Belgium: income year 2026 vs 2027
| Parameter | 2026 | 2027 | Status |
|---|---|---|---|
| Tax-free amount (belastingvrije som), base | €4,945 (indexed €11,550) | <strong>€4,990</strong>; indexed amount pending | Adopted |
| Child supplement, base: 1 / 2 children | €935 / €2,250 | €1,005 / €2,260 | Adopted |
| Marital quotient cap, base (spouses under 66) | €5,860 | €5,030 | Adopted |
| Wages of working pensioners | Progressive rates | <strong>33%</strong> separate rate | Adopted (pay from 1 Jan 2027) |
| Ondernemersaftrek (entrepreneur deduction) | None | 10% of profits, cap €311 base | Adopted |
| Fiscal werkbonus, part A / part B | 33.14% / 63%; ceiling €970 base | Unchanged (35% / 72% from 2028) | Adopted |
| Brackets 25 / 40 / 45 / 50% | Thresholds €16,720 / €29,510 / €51,070 | Indexed; pending | Indexation |
| Lump-sum professional expenses | 30%, max €6,070 | Indexed; pending | Indexation |
| Employee social security (RSZ) | 13.07% | No change found | — |
| Special social security contribution (BBSZ) | Household-based, max €731.28 | Unchanged (individual, max €365.64 from 2028) | Adopted |
Base = the non-indexed amount in the income tax code (WIB 1992); the amount that applies is base × the index coefficient, not yet published for 2027. Years are income years: 2027 income is assessed in 2028 (aanslagjaar / exercice d'imposition 2028).
Employees and families
Tax-free amount and children
The base tax-free amount rises by €45. At the 2026 index coefficient that is about €105 more tax-free income, worth about €28 a year (25% rate plus a 7% municipal surcharge). The one-child supplement rises by €70 base, about €40–45 a year; for two children the base rises by only €10. The tax-free amount keeps growing: base €5,070 in 2028, then €14,450 and €15,600 after indexation in 2029 and 2030.
Single-earner couples pay more
The marital quotient (huwelijksquotiënt / quotient conjugal) shifts part of a working spouse's income to a partner with little or no income, where lower rates apply. For spouses under 66, the base cap falls about 14%, from €5,860 to €5,030, then to €4,190 in 2028 and €3,350 in 2029. Where the transfer is maxed out, around €2,000 less income can move in 2027, which can cost roughly €300–500 a year, depending on the earner's marginal rate.
Working pensioners and low earners
The 33% rate applies to wages paid from 1 January 2027 and generally pays off when pension and wages together reach the 45% and 50% brackets. The fiscal werkbonus, a tax credit worth a share of the social werkbonus (the cut in employee contributions on low wages), already rose in income year 2026: 63% of part B, up from 52.54%, with a €970 base ceiling, up from €765. Nothing changes in 2027; the next step comes in 2028.
Self-employed
A 10% entrepreneur deduction
From income year 2027, the self-employed can deduct 10% of their profits as an ondernemersaftrek, capped at €311 base; the indexed cap is pending. The base cap rises to €415 from income year 2029. Advance tax payments have not been compulsory for the self-employed since income year 2026, so there is no surcharge for skipping them.
Expats and relocants
What matters if you move to Belgium
If your spouse does not work in Belgium, common in the first years after a move, the smaller marital quotient hits you directly, and it shrinks again in 2028 and 2029.
The special tax regime for inbound taxpayers and researchers was revised with effect from 2025. We found no further change for 2027; if you use it, check that your employer applies the current rules.
Payroll withholding for 2027 follows the indexed amounts, so recheck your net pay once they are published.
Your next return still uses 2026 amounts
FAQ
What changes in Belgian income tax in 2027?
Under the reform law of 15 July 2026: a base tax-free amount of €4,990 (from €4,945), a 33% rate on wages of working pensioners, a 10% entrepreneur deduction, higher child supplements and a lower marital quotient cap (base €5,030, from €5,860).
What is the difference between the base and the indexed tax-free amount?
The law states base amounts, multiplied each year by an index coefficient. For 2026, the base €4,945 becomes €11,550. For 2027, the base is €4,990; the indexed figure depends on a coefficient FPS Finance has not yet published.
How are working pensioners taxed from 2027?
Employees who also receive a retirement or survivor's pension pay a separate 33% on wages paid from 1 January 2027, without the overtime reduction. Self-employed people and company directors are excluded.
Does the fiscal werkbonus change in 2027?
No. The rise to 63% of part B with a €970 base ceiling already applies from income year 2026. The next step, 35% of part A and 72% of part B, comes in income year 2028.
