Key Points in Plain Language
- Moving to the Netherlands part-way through the year means filing the M-form (migration-year tax return) and declaring your worldwide assets as of the reference date.
- A draft return may show a refund (e.g. €[Refund Amount 1]) before global assets are added. After including your holdings, the refund may reduce to about €[Refund Amount 2] under the Savings and Investments (Box 3) regime.
- Typical assets: bank savings in Country X and Country Y, a home in City A, and an older vehicle abroad — together roughly €[Total Assets Value].
- Conservative rounding (for instance, €[Rounded Figure 1] or €[Rounded Figure 2], about twice the exemption threshold) helps maintain accuracy and defendability.
- Only the portion of the year you were resident in the Netherlands (~[Residence Fraction of Year] %) is taxed there.
- Market checks for homes in City A confirmed estimates near €[House Value Range], supporting the rounded value and preserving the refund.
The Situation
When someone immigrates mid-year, their tax adviser requests a summary of global assets as of the reference date. The initial draft return (issued in [Month of Communication]) projected a refund near €[Refund Amount 1]. To finalize the return, the adviser asked for values of all assets held on the reference date, converted at the appropriate exchange rates.
Summary of reported assets:
- Bank savings in Country X: approx. €[Value X]
- Bank savings in Country Y: approx. €[Value Y]
- Residential property in City A: single-storey family home, estimated at €[House Value Range]
- Older vehicle abroad (purchased [Vehicle Year]): approx. €[Vehicle Value]
Rounded total ≈ €[Total Assets Value], and therefore the expected refund becomes about €[Refund Amount 2].
How the Numbers Were Estimated
The initial estimate for the property was near €[Initial High Estimate], but a review of listings on local real-estate platforms showed comparable homes priced between €[Low Market Value] and €[High Market Value]. A midpoint value of about €[House Value Range] was selected.
For simplicity and defensibility, the total was then rounded to €[Rounded Figure 2] — approximately twice the exemption threshold. The final working total of €[Total Assets Value] reflects a reasonable, cautious estimate.
Why Transparency Matters
Dutch tax law emphasises honest reporting of assets. Small errors can generally be corrected administratively, but deliberate omissions may result in penalties. For moderate asset holdings, providing well-documented estimates is both practical and safe. It remains important to retain supporting evidence (bank statements, property listings, vehicle records) in case of a tax-office query.
Keeping It Practical
A fluctuation of a few thousand euros in declared assets usually has only a marginal effect on the refund. Declaring around €[Rounded Figure 1–2] therefore remains realistic, compliant and likely to preserve the refund outcome.
What Happens If Wealth Is Higher?
Only assets exceeding the exemption threshold fall under Box 3. The tax applies to an “assumed return” on assets, prorated for your period of residence in the Netherlands. At higher wealth levels (e.g., €[High Wealth Example]), the refund may convert into a tax payment of several thousand euros — demonstrating the sensitivity of the refund outcome to asset value.
Glossary
Migration-Year Tax Form (M-form)
The specific tax return used when an individual moves into or out of the Netherlands during the calendar year. It allocates income and tax liability between the non-resident and resident periods.
Savings and Investments (Box 3)
The Dutch tax category that applies to assumed returns on savings, investments and secondary real estate above a certain exemption threshold. Unlike taxes on actual investment income, it uses a fictitious yield. (belastingdienst.nl)
Exemption Threshold
The tax-free allowance for Box 3: for example €57,000 (as one person) in some recent years. (taxsavers.nl)
Tax Partner
In the Netherlands, a person who shares tax filing status with you (often spouse or registered partner) and can jointly allocate allowances and assets for tax purposes.
Partial-Year Residency
When you have moved to the Netherlands during the year, only the portion of the year you were resident is taxed as a resident under the M-form.
Reliable Sources (Checked October 2025)
- Income in Box 3 – Dutch Tax and Customs Administration: https://www.belastingdienst.nl/wps/wcm/connect/en/income-in-box-3/online (belastingdienst.nl)
- How Dutch wealth tax works in 2023-2024 – The TaxSavers: https://taxsavers.nl/dutch-tax-system/assets/ (taxsavers.nl)
- Netherlands box 3 tax rates – Blue Umbrella FAQ: https://www.blueumbrella.nl/faq/income-tax/income-tax-rate-in-the-netherlands/box-3-tax-rates (blueumbrella.nl)
- Migration tax return guidance – NetherlandsWorldwide: https://www.netherlandsworldwide.nl/tax-return-abroad/year-movement-netherlands (netherlandsworldwide.nl)
- Draft legislation to replace Box 3 regime – KPMG: https://kpmg.com/us/en/taxnewsflash/news/2025/05/netherlands-draft-legislation-replace-box-3-regime-lower-house-parliament.html (kpmg.com)
- YouTube: How to apply tax refund in the Netherlands as an expat – https://www.youtube.com/watch?v=dLUYEet4p4c (youtube.com)
This article is provided for informational purposes only and does not constitute formal tax advice. Figures in brackets [ ] must be replaced with actual data relevant to the individual’s situation. It is strongly recommended to consult a licensed Dutch tax adviser prior to filing your M-form.
My Diary - Leonardo Cardillo 