Overview: the Dutch tax system
The Dutch tax system divides income into three “boxes”: Box 1 (income from work and home), Box 2 (substantial interest in a company), and Box 3 (savings and investments). Most expats primarily deal with Box 1, though Box 3 becomes relevant if you hold significant assets.
The tax year runs from January 1 to December 31. Your employer withholds payroll tax throughout the year, and the annual tax return reconciles what you owe versus what was already paid.
Which form do you need?
M-form (Migration form)
For the year you arrived in or left the Netherlands. Covers both Dutch and worldwide income for that transitional year. Cannot be filed online — must be done on paper or through a tax advisor.
C-form (Standard return)
For full tax years where you were a Dutch resident for the entire year. Can be filed online through Mijn Belastingdienst using your DigiD.
Common deductions for expats
These are the most relevant deductions that expats frequently miss:
- Mortgage interest (eigenwoningforfait): If you own a home in the Netherlands, mortgage interest is deductible from your Box 1 income. This is often the largest deduction for homeowners.
- Healthcare costs (zorgkosten): Specific medical expenses above a threshold amount can be deducted, including costs not covered by insurance, prescribed medication, and travel to medical appointments.
- Study costs: Costs for education directly related to your current or future profession may be deductible, though the rules have become more restrictive in recent years.
- Charitable donations (giften): Donations to registered Dutch charities (ANBI) above the threshold are deductible. Periodic donations (committed for 5+ years) have no threshold.
- Commuting costs: Public transport commuting costs may be reimbursed tax-free by your employer, and unreimbursed costs in specific situations may be deductible.
30% ruling holders
If you have the 30% ruling, most of these deductions are already covered by the tax-free allowance. However, mortgage interest is still deductible on top of the 30% ruling, making homeownership particularly tax-efficient for ruling holders.
How to file step by step
- Get your DigiD: You need a DigiD (digital identity) to file online. Apply at digid.nl — you'll need your BSN number. Activation takes about a week.
- Gather your jaaropgave: Your employer provides a jaaropgave (annual statement) by February, showing your gross salary, tax withheld, and social contributions for the year.
- Log in to Mijn Belastingdienst: The tax authority pre-fills much of the return with data from your employer, bank, and mortgage provider. Review the pre-filled data carefully.
- Add deductions: Enter any additional deductions not pre-filled (healthcare costs, charitable donations, study costs).
- Review and submit: The system calculates your refund or amount owed. Review carefully, then submit. You typically receive the result within 3 months.
Key deadlines
| Deadline | Action |
|---|---|
| February 28 | Employer provides jaaropgave |
| March 1 | Online filing opens at Mijn Belastingdienst |
| May 1 | Standard filing deadline |
| September 1 | Extended deadline (if requested before May 1) |
The M-form: your arrival year
Your first year in the Netherlands requires the M-form, which is more complex than the standard return. It asks for worldwide income from the entire year, split between your Dutch and non-Dutch periods.
The M-form cannot be filed online and is often sent by the Belastingdienst later than the standard invitation. Many expats choose to hire a tax advisor for their first M-form, as incorrect filing can lead to penalties or missed refunds.
Don't skip the M-form
Even if you only lived in the Netherlands for a few months, filing the M-form can result in a significant refund. Your employer likely withheld tax as if you worked the entire year, so you may have overpaid.
Frequently asked questions
Do I need to file a tax return in the Netherlands?
If you receive a letter from the Belastingdienst inviting you to file, you must do so. Even without an invitation, you should file if you're eligible for deductions or refunds (mortgage interest, healthcare costs, etc.), or if you arrived or left the Netherlands during the tax year.
What is the difference between the M-form and C-form?
The M-form (migratieformulier) is for the year you arrived in or left the Netherlands. It covers both your Dutch and foreign income for that year. The C-form is the standard annual return for full-year Dutch tax residents.
When is the Dutch tax return deadline?
The standard deadline is May 1 following the tax year. For the 2025 tax year, the deadline is May 1, 2026. You can request an extension until September 1. M-forms have different deadlines and are typically sent later.