Dutch fiscal partnership can reduce your combined tax bill, but the largest refund on your own return is not necessarily the best result for you as a couple. How you allocate eligible deductions and taxable income from savings and investments can make a difference. When I prepare your returns, I look at them together: what can be allocated, how does it affect the total, and are there consequences for benefits?
Being tax partners is usually determined by the rules
For couples who both live in the Netherlands, the general rule is that marriage or a registered partnership makes you fiscal partners, also called tax partners. If you live together without either, sharing an address is not enough on its own. There needs to be another qualifying connection, such as a notarised cohabitation agreement, a child together, or a home you jointly own and live in. Registration as pension partners can also count.
You can also become tax partners without a child together or a cohabitation agreement. Suppose you and your daughter under 18 move in with your boyfriend. If both adults and the child are registered at that address, this may be enough. The child need not be yours together. Commercial room rental can qualify for an exception, requiring a written tenancy agreement and a request. I check whether it applies; describing someone as a housemate does not settle their tax status.
The start date deserves attention. If you share an address from January and marry in August of the same year, your tax partnership can start in January. When partnership covers only part of a year, choosing full-year treatment may allow shared tax items to be allocated between you.
Separation needs a different check. For married couples, fiscal partnership ends only once a divorce or legal separation request has been filed and you are no longer registered at the same address. Moving out alone is not enough. If you have separated or one partner lives abroad, I establish which partner rules apply before comparing allocations.
I prepare both Dutch income tax returns and compare how to allocate deductions and taxable income from savings and investments between you. I look at your combined tax bill and, where relevant, the effect on your benefits.
Contact me to have your returns handled together.
Why I do not automatically give the higher earner every deduction
Partners for the full year, including those who qualify and choose full-year treatment, can allocate certain items between them. These include the net income and deductions relating to your main home, qualifying charitable donations and deductible healthcare costs. Salary, pension and business profit stay with the person who earns them. A self-employed person cannot simply move half their profit to a lower-earning partner.
For your home, the allocation covers mortgage interest and other qualifying costs together with the eigenwoningforfait, the amount added to your taxable income for owning your main home. I look beyond the tax bracket. Income-dependent tax credits can change the result too, so sharing a deduction can work better than allocating all of it to one person.
Consider two possible outcomes. Under allocation A, you receive a €1,800 refund and your partner pays €400: a combined refund of €1,400. Under allocation B, you receive €1,300 and your partner receives €300: €1,600 together. Your own refund is smaller, yet you are €200 better off as a couple.
Allocation comes after checking eligibility. Moving interest to your partner cannot make a non-deductible loan deductible. If you have bought a home or sold a previous property, I first check which mortgage interest qualifies for relief.
Uneven savings can make partnership useful
Suppose you have €90,000 in savings on 1 January 2026 and your partner has €10,000, with no other box 3 assets or debts. Box 3 is the part of the Dutch tax system covering savings and investments. For full-year fiscal partners, including those choosing full-year treatment, the joint asset exemption in 2026 is €118,714. Your combined €100,000 falls below it.
Without fiscal partnership, each person has a separate €59,357 exemption. The person with €90,000 cannot use the other’s unused allowance. The advantage here comes from how unevenly the savings are held. Investments or a second property call for a broader box 3 review than simply comparing assets with the exemption.
Above the exemption, tax credits matter too. Since 2025, taxable box 3 income has counted towards the reduction of the general tax credit. Your asset balance is not itself that income: the calculation uses your assessed box 3 income. Two allocations producing the same box 3 tax can therefore leave you with different overall bills. I compare them alongside your other income and tax credits.
Partnership can also reduce deductions or benefits
For non-periodic charitable donations and qualifying healthcare expenses, your combined income can raise the threshold that applies before costs become deductible. High medical expenses and a low personal income do not necessarily mean a large deduction if your partner earns considerably more. I check which costs qualify, the combined threshold and then the allocation.
A partner with no income is not automatically entitled to a tax refund either. Since 2023, the general tax credit is no longer paid out to a lower-earning partner born in 1963 or later on the basis of the other partner’s tax liability. For someone born before 1963, a payment may still be available if the conditions are met.
I assess Dutch income-related benefits, or toeslagen, separately. Fiscal partnership and benefit partnership do not have identical conditions or start dates. A tax saving can coincide with lower benefits because a partner’s income or assets count. Where relevant, I include your Dutch benefits and allowances in the review.
Have your two returns considered together
Would you like me to work out which allocation suits your situation? As part of my Dutch income tax return service, I check your partner status, the shared tax items and the outcome of both returns. Briefly tell me about changes such as moving in together, buying a home or separating. I explain the work and fees before starting and submit the returns only after you have both approved them.