Belgium Tax Benefits: Marriage, Children and Tax-Free Income

Your family situation can make a significant difference to how much income tax you pay in Belgium. Marriage, legal cohabitation and having dependent children can all affect your tax calculation.

However, the Belgian tax system is more complicated than simply saying that married people always pay less tax. The benefit depends on the income of both partners, the number of dependent children and other personal circumstances.

Here is how the main tax benefits work in 2026.

Marriage and legal cohabitation in Belgium

For Belgian income tax purposes, married couples and people who have officially declared legal cohabitation are generally treated in a similar way.

One important benefit is the marital quotient, known in Dutch as the “huwelijksquotiënt.” This system can apply when one partner has little or no professional income.

Under the system, part of the income of the higher-earning partner can be allocated for tax purposes to the partner with lower income, within the legal limits. This can reduce the overall tax burden because the income may be taxed at lower rates.

The benefit is not the same for every married or legally cohabiting couple. When both partners have significant income, the effect can be limited or disappear.

How much income is tax-free in Belgium in 2026?

For income earned in 2025 and declared in the 2026 tax return, every taxpayer has a basic tax-free allowance of 10,910 euro.

This means that the first 10,910 euro of taxable income is not subject to personal income tax.

The amount can increase when you have dependent children.

The current additional tax-free amounts for dependent children are:

•  One child: 1,980 euro
•  Two children: 5,110 euro
•  Three children: 11,440 euro
• Four children: 18,510 euro
• Each additional child: 7,070 euro

These amounts are added to the basic personal tax allowance. For example, a taxpayer with four dependent children can have a total tax-free amount of 29,420 euro before taking other possible adjustments into account.

There can also be additional increases in specific situations, such as when a dependent child is under three years old and certain childcare expenses are not claimed.

Having children does not mean your entire salary is tax-free

This is an important point that is often misunderstood.

The tax-free allowance does not mean that someone earning 50,000 euro automatically pays no tax on the remaining income.

Belgium uses progressive income tax rates. For income earned in 2025, the federal tax brackets range from 25% to 50%, depending on the level of taxable income. The personal tax allowance is then taken into account when calculating the final tax.

Your final bill can also be affected by social security contributions, professional expenses, municipal taxes and other tax reductions or deductions.

This is why two people with the same gross salary can end up with different final tax bills.

Single parents can receive an additional tax benefit

Belgium also provides additional tax advantages in certain situations for a single parent with dependent children.

This is separate from the standard increase for dependent children and can increase the tax-free amount further.

The exact benefit depends on the person’s circumstances and whether the legal conditions for the single-parent allowance are met.

What about people who simply live together?

There is an important difference between legal cohabitation and simply sharing a home.

Two people who live at the same address but have not married or officially declared legal cohabitation are generally treated as separate taxpayers.

They cannot use the marital quotient simply because they live together.

Their income is therefore generally assessed separately, and the tax treatment of their children depends on the applicable rules concerning dependent children and their actual family situation.

In other words, registering at the same address does not automatically give a couple the same tax status as marriage or legal cohabitation.

Child benefits are separate from income-tax allowances

Parents in Belgium may also receive family benefits, but these should not be confused with the federal income-tax allowance for dependent children.

Family benefits are administered through the regions and can include monthly payments and other support for children.

In Flanders, for example, the system is known as the Groeipakket.

The income-tax allowance works differently: instead of being a direct monthly payment, it increases the portion of taxable income that is exempt from personal income tax.

What happened to the Belgian mortgage tax benefit?

The old rules surrounding the Belgian housing bonus, or “woonbonus,” are important because many older articles still describe them as if they apply to new mortgages.

They do not. In Flanders, there is no longer a tax reduction for mortgage loans taken out after December 31, 2019. Existing loans that qualify under the older rules can continue to receive the applicable tax treatment.

For people buying their only and primary home in Flanders today, the situation is different.

Since January 1, 2025, the registration tax for an eligible sole and own home has been reduced to 2%. For purchase agreements from January 1, 2026, additional conditions apply, including requirements concerning registration at the property.

This means that someone buying a home in Flanders in 2026 should not expect a new mortgage tax deduction simply because they are married or legally cohabiting.

Tax rules are changing again

Belgium has also introduced a broader personal income-tax reform.

For income year 2026, the basic tax-free allowance is scheduled to rise to 11,180 euro. The increase is part of a gradual reform that will raise the tax-free amount over several years.

The tax-free supplements for dependent children are also being changed gradually, particularly for families with one or two children.

Because of these changes, older Belgian tax articles can contain figures that are no longer correct for current tax years.

Marriage or legal cohabitation can provide tax advantages in Belgium, particularly when there is a large difference between the partners’ incomes. The marital quotient can allow part of one partner’s income to be allocated to the lower-income partner under the applicable rules.

Having dependent children can also substantially increase the tax-free portion of income. For income earned in 2025 and declared in 2026, the basic tax-free allowance is 10,910 euro, with additional amounts ranging from 1,980 euro for one child to 18,510 euro for four children.

However, there is no single tax result for every family. Your income, partner’s income, number and age of children, municipality, professional expenses and other deductions can all affect the final amount.

For an exact calculation, taxpayers can use the Belgian government’s MyMinfin services or the official tax calculation tools rather than relying on a simple salary-versus-family-size calculation.