Bouwdepot: your deduction in Box 1

What is a bouwdepot, and what does it mean for your tax return?

A bouwdepot is money from your mortgage. It sits in a separate account, waiting to pay for a renovation or a new-build home. Your lender pays out from it as the work progresses.

For up to two years, the depot and the loan behind it both stay in Box 1.

That timing matters for tax. The Belastingdienst lets you deduct the interest on eigenwoningschuld, your home-acquisition debt. The interest you receive on the depot comes off that deduction. The window runs for two years. When it starts depends on the depot type. What is still unspent when the window ends moves to Box 3. Get it wrong, and you either miss a deduction or declare too little wealth.

Take Liam. He moved to the Netherlands three years ago and just bought an older canal-side house. He is renovating it. His mortgage includes a €35,000 verbouwingsdepot for the works. We use his depot to show exactly how the rules apply, start to finish.

This guide covers a construction depot held inside a Box 1 eigenwoning mortgage. It does not cover a savings deposit unrelated to your mortgage, or funds held for a rental property. Those follow different rules. Holding a rental property or savings unrelated to your mortgage? Read our Box 3 guide.

The deduction assumes you are a Dutch resident taxpayer or a qualifying non-resident taxpayer. Move abroad without qualifying status and you can no longer deduct the mortgage interest on your home. So check with us before you leave. A qualifying non-resident taxpayer earns almost all income in the Netherlands and files here. Box 1 taxes income from work and your home. Box 3 taxes savings and investments. Our owning a home overview explains how tax works on a finished home.

Box 1 or Box 3: how does the Belastingdienst classify your bouwdepot?

For up to two years, your whole bouwdepot loan counts as eigenwoningschuld in Box 1. After that, the part still in your depot moves to Box 3.

Liam's €35,000 sits in his lender's bouwdepot account. During his two years, the whole loan counts as eigenwoningschuld in Box 1. The moment his lender pays a builder or supplier out of that depot, that part is ordinary eigenwoningschuld. Only what is still unspent when the window ends moves to Box 3.

Two rules decide how much interest Liam can actually deduct. The tweejaarsregeling gives the netting and the unspent balance a two-year window.¹ The part your lender has already paid out keeps its interest deduction. The clock itself starts at a different moment depending on the depot type.

For a verbouwingsdepot like Liam's, the two-year clock starts the day the depot is opened.¹ For a nieuwbouwdepot, the clock starts the day you sign the purchase or construction agreement.² Have no loan yet at that point? Then it starts the day you sign for the loan at the notary.

The table below lines up both depot types side by side. Watch the one asymmetry that catches people out most: the six-month rule, or zesmaandsgoedkeuring.

What if your home is still under construction or stands empty?

A home under construction only qualifies as your eigen woning if you meet the driejaarseis. Eigen woning means your main home for tax purposes. That is the three-year test. The same applies to a newly bought home that stands empty. You move in during the same calendar year. Or it is genuinely realistic that you will move in within the next three years.⁴

Does Liam need to worry about the driejaarseis too? Not anymore, his house was already livable when he moved in. Many bouwdepot owners are still building or renovating first, so here is what applies to them.

While your home qualifies, the eigenwoningforfait, the notional rental value added to your income, is €0. You pay no forfait on a home you cannot yet live in.⁴

Suppose a posting abroad delays your renovation past year three. Moving in is no longer realistic, so your home and its debt move to Box 3 for that year. The Belastingdienst checks the driejaarseis fresh every calendar year. Your home can move back to Box 1 once moving in becomes realistic again.

One more edge case is worth knowing, especially if you bought raw land before building started:

Working out Liam's deduction, step by step

Liam's verbouwingsdepot is €35,000, at 4% interest. In month seven he pays about €117. He receives about €47 from his depot. He deducts the difference, about €70.

Liam opens his verbouwingsdepot on 1 February 2026. His depot pays the same interest as his mortgage, which is how most lender products work. While the money sits in the depot, the two amounts cancel out. What he deducts is the interest on the part his lender has already paid out. The more the builder invoices, the smaller the depot and the larger that deductible part.

One exception comes first. In the first six months of a verbouwingsdepot the Belastingdienst does not net the two amounts. Everything Liam pays is deductible. From month seven the netting starts.

Here is his depot over time:

In the first six months Liam deducts all the interest he pays. From month seven he deducts the interest on what has actually been paid out. His total depends on how fast the work is invoiced.

What should you check before you file?

Start with your depot statement. Confirm your depot type, renovation or new build. Then check the date it opened or the date you signed, and how much interest you paid and received this year.

Then check where your home itself stands. Still under construction or standing empty? Confirm you still meet the driejaarseis, so your home and its debt stay in Box 1 rather than shifting to Box 3.

Valuation costs, mortgage-advice fees and notary fees for the loan are deductible once, in the year you pay them.⁵ The deduction covers them to the extent they relate to your eigenwoningschuld. Book your free call and we sort it together.

How tax on your own home works is on our overview of owning a home. Want us to do it for you? See how we handle your Dutch tax return.