Does a mortgage reduce my Box 3 tax?

Generally no, because the mortgage on your primary home falls in Box 1 (deductible interest). It does not offset your Box 3 assets.

Box 3 for Expats: How It Changes Rent vs Buy (2026)

Q: Is my home taxed in Box 3?

No. Your primary residence (eigen woning) falls in Box 1. It is not taxed as an asset in Box 3.

Q: What happens after my 30% ruling ends?

You become a regular resident taxpayer. Your worldwide savings and investments will be taxed in Box 3.

Box 3 for Expats: The Hidden Lever in Rent vs Buy

For expats in the Netherlands, the decision to rent or buy is often complicated by a specific tax rule: Box 3 (Tax on Savings and Investments).

If you are a renter, you likely have significant savings or investments (since you haven't locked them up in a house). Under standard Dutch rules, these are taxed heavily. However, if you benefit from the 30% ruling, you may be exempt from this tax, shifting the math in favor of renting.

Why Box 3 Matters in Rent vs Buy

In our calculator, the "Rent" scenario assumes you invest the difference between your rent and what you would have paid for a mortgage.

Standard Situation: Your investment returns are taxed in Box 3 (roughly 36% tax on a fictitious gain of ~6%, resulting in ~2% wealth tax per year). This drags down your rental wealth accumulation.
Expat Situation (Partial Non-Resident): If you have the 30% ruling, you can opt for "partial non-resident taxpayer status". This means you do not pay Box 3 tax on foreign savings and investments (until the ruling expires).

How to Model This

1. Identify Your Status

Do you have the 30% ruling?

Yes: You can likely set the Box 3 tax rate to 0% for the duration of your ruling.
No: use the standard rate (default in calculator).

2. Adjust the Calculator (#box3)

Find the Box 3 Effective Tax Rate input.

Default: It's usually set around ~2% (representing the effective drag on wealth).
With 30% Ruling: Set this to 0%.
Duration: Remember that the 30% ruling lasts only 5 years (as of 2026 rules). After that, you revert to standard taxation.

Common Pitfalls

Double Counting

Don't subtract tax from your "Investment Return" input AND use the Box 3 input.

Best Practice: Enter your gross expected market return (e.g., 7%) in the Investment Return field, and let the Box 3 input handle the tax drag.

Wrong Horizon

If you plan to stay 10 years, but your 30% ruling ends in 2 years, you shouldn't model 0% tax for the whole period.

Solution: Use a weighted average, or model conservatively with the standard tax rate if you plan to stay long-term.

Sensitivity: When Box 3 Flips the Decision

This tax is often the "tie-breaker".

If you are exempt from Box 3, Renting + Investing becomes significantly more attractive because your compound interest grows tax-free.
Once you become a regular taxpayer, buying often catches up because the equity in your primary home is Box 3 exempt for everyone.

FAQ

Is my home taxed in Box 3?

No. Your main residence falls into Box 1. It generates a small taxable income ("eigenwoningforfait"), but it is exempt from the wealth tax of Box 3.

What happens after my 30% ruling ends?

You become a full resident taxpayer. Your global assets (above the threshold) will be taxed in Box 3. This often makes buying more attractive at that point, as it moves capital from taxable Box 3 to tax-exempt Box 1 (home equity).