Being fiscal partners under Dutch tax law can reduce your tax bill. You can allocate certain shared tax items between you, such as the deduction for your main home. Your salary stays with you. Some deduction thresholds use your combined income, and benefit rules need their own check. Here is how I would work through the decision before submitting your returns.
Are you fiscal partners in the Netherlands?
Fiscal partnership is a status set by Dutch tax law. It is not an option that any couple can switch on when it saves money and switch off when it does not. Marriage or a registered partnership will generally make you fiscal partners.
For unmarried couples, sharing an address is not enough on its own. You must meet an additional condition, such as having a notarised cohabitation agreement, having a child together, or jointly owning the home where you both live. Recognition of the other person’s child and registration as pension partners can also matter. There are separate conditions and exceptions for blended families.
For example, Alex and Maya rent an apartment together. They have no children, no notarised cohabitation agreement and no pension partnership. They were not fiscal partners previously. Their shared address alone does not make them fiscal partners. If they later buy a home together and both live there, their position changes.
You can have only one fiscal partner at a time. This article focuses on couples who both live in the Netherlands. If one of you lives abroad, or you moved into or out of the country during the year, check the additional rules before using the examples below. My migration and living abroad service covers those Dutch tax questions.
What can you split between you?
If you are fiscal partners for the whole year, or qualify and choose whole-year treatment, you can allocate certain items between you. These include the net amount relating to your main home, qualifying charitable donations and deductible healthcare costs. You can also allocate the joint savings and investments tax base in box 3.
For your main home, the relevant amount includes both deductible expenses, such as qualifying mortgage interest, and the taxable addition known as the eigenwoningforfait. This is an amount added to your income because you own and occupy the home. You allocate the net result, rather than simply moving one mortgage interest payment to the other person.
Suppose the home section of your return produces a €6,000 deduction. You could allocate €3,000 to each partner, all €6,000 to one partner, or use a different split. The combined allocation must always add up to 100%.
I would compare at least three versions: the full deduction for you, the full deduction for your partner, and a split between you. The result to compare is the combined tax position after both returns have been calculated.
Why the higher earner is not always the best choice
Putting every deduction against the higher salary sounds sensible. It can work, but it is not a rule. Income-related tax credits, income in other tax boxes and limits on the rate of tax relief can change the result.
Remember that a deduction is not a refund of the same amount. A €6,000 deduction reduces taxable income by €6,000. It does not put €6,000 back into your bank account.
Here is a simple way to compare the results. Under split A, you receive a €1,800 refund while your partner pays €400. Together, you receive €1,400. Under split B, you receive €1,300 and your partner receives €300. The combined refund is €1,600. Split B leaves you €200 better off as a couple, even though your own refund is smaller. These figures illustrate how to compare results; they are not a calculation using Dutch tax rates.
Each of you still receives an individual tax assessment. If the refund goes to one partner while the other has to pay, agree how you will settle that between yourselves.
Your salaries remain your own
Fiscal partnership does not let you pool your earnings and divide the total in half. Employment income, pension income, benefits and business profits remain with the person who earned or received them. Personal annuity contributions cannot simply be transferred to the other partner either.
If you earn €70,000 and your partner earns €25,000, you cannot report €47,500 each. You can only allocate the specific shared items that the Dutch return allows you to split.
Nor does a tax allocation change legal ownership. Putting more of the joint box 3 tax base in one return does not transfer a savings account, investments or a property into that person’s name.
Savings: using both tax-free allowances
Under the standard box 3 calculation, part of your savings and investments is covered by a tax-free allowance. For 2026, this is €59,357 per person, or €118,714 for fiscal partners with whole-year treatment.
Suppose you have €90,000 in savings on 1 January 2026 and your partner has €10,000. Neither of you has other box 3 assets or debts. As fiscal partners for the whole year, your combined €100,000 is below the joint allowance. Without fiscal partnership, the person with €90,000 cannot use the other person’s unused allowance.
The benefit in this example comes from the uneven ownership of the savings. If each of you already holds less than the individual allowance, combining the allowances does not create an extra saving on that point. Larger portfolios need a fuller box 3 calculation; the allowance alone does not tell you what tax you owe.
The drawback: higher deduction thresholds
Some expenses only become deductible above an income-based threshold. With whole-year fiscal partnership, the threshold for qualifying healthcare costs and ordinary charitable donations takes both partners’ incomes into account.
That can reduce your deduction. If you have a low income and substantial healthcare expenses, a higher-earning partner can push up the threshold. On the other hand, qualifying expenses for both of you are considered together.
You also need to establish which expenses qualify in the first place. A medical bill is not automatically deductible. For example, the mandatory excess on Dutch health insurance, the verplicht eigen risico, is not deductible. Work out the qualifying costs first, apply the threshold, and only then consider how to allocate the deduction.
A non-working partner does not automatically receive a tax credit payment
An older explanation of Dutch fiscal partnership may suggest that a partner with little or no income can receive the general tax credit through the other partner. That is no longer the general position.
For the lower-earning partner born in 1963 or later, this payment has been abolished since 2023. For someone born before 1963, a tax credit payment may still be possible. It depends on their own income and, among other things, the tax payable by the other partner.
If your household has one salary, do not build an automatic annual payment for the non-working partner into your budget.
Check Dutch benefits separately
Your tax partner is often also your partner for Dutch benefits, known as a toeslagpartner. However, the rules are not identical. A benefits partner’s income and, for some benefits, assets can affect entitlement. Healthcare or housing benefit may fall or stop when the relevant partner rules apply.
Choosing whole-year fiscal partnership for income tax does not by itself decide when you become benefits partners. Check this separately when you move in together or separate. I explain the help available on my page about Dutch benefits and allowances.
Before you submit both returns
Start with the dates. When did you register at the same address, marry or buy your home? Fiscal partnership can reach back to an earlier point in the same calendar year. For example, a couple who marry in August and have been registered together since 1 January of that year are tax partners from 1 January.
Then complete the underlying figures for both people: income, the main home, assets and debts on 1 January of the tax year and qualifying expenses. Compare allocations only once that information is complete. Keep a record of the agreed split and make sure both returns match, even if you submit them separately.
Would you like me to prepare your tax returns and work out the best allocation? As part of my income tax return service for individuals, I review your circumstances and apply the most favourable allocation. This makes it clear which deductions you can claim and which split works best for you.