The 2026 brackets
Employment income, pensions and your own home sit in box 1. For people under the AOW age, box 1 has three brackets in 2026:
| Taxable income | Rate |
|---|---|
| Up to €38,883 | 35.75% |
| €38,883 to €78,426 | 37.56% |
| Above €78,426 | 49.50% |
The first bracket is mostly national insurance: 27.65% for the state pension (AOW), survivor's benefit (Anw) and long-term care (Wlz), plus a small slice of income tax. Those contributions stop at €38,883, which is why the second bracket is only slightly higher.
The brackets apply to slices, not to your whole income. Someone on €90,000 pays 35.75% on the first €38,883, 37.56% on the next €39,543, and 49.50% only on the last €11,574. Before credits that is about €34,500, an average of about 38%. If you have the 30% ruling, the tax-free allowance is taken off first and the brackets apply to what is left.
The credits that bring the bill down
Two heffingskortingen are deducted from the tax itself, not from income, so they are worth their face value:
- General tax credit (algemene heffingskorting): up to €3,115, reduced by 6.398% of income above €29,736 and gone at €78,426.
- Labour tax credit (arbeidskorting): builds up to €5,685 at an income of about €45,592, then shrinks by 6.51% of income above that and reaches zero at €132,920.
- Working parents with a child under 12 may also get the income-dependent combination credit (IACK), up to €3,032.
Your employer applies the credits in payroll, which is why your payslip already shows a net figure close to the real thing. The salary calculator uses exactly these brackets and credits.
The letters, and what they want
- Aangiftebrief: the invitation to file a return, usually in February. Once you have one, filing is mandatory.
- Voorlopige aanslag (provisional assessment): an estimate for the current year, either a monthly refund (for example for mortgage interest) or a monthly payment. You can request or change one at any time.
- Definitieve aanslag (final assessment): the settlement after your return, showing what you get back or pay. Check it against your return. You can object within six weeks.
- Blue envelope with "Toeslagen": it is about benefits, not income tax. See toeslagen explained.
Filing: who, when and how
The return for year X opens on 1 March of year X+1 and is due before 1 May. You can request an extension to 1 September; interest (belastingrente, 5% in 2026) may apply on tax you still owe. Most of the return is pre-filled from your employer, bank and the land registry. You file online in Mijn Belastingdienst with a DigiD, and you need a DigiD for almost everything, so request one early.
You must file if you receive a letter, or if you expect to owe more than a small threshold. Filing without a letter is voluntary and often pays: a partial year of employment, mortgage interest on your own home, study costs in older years, alimony or a partner with little income can all produce a refund. If in doubt, run the return online; it shows the result before you submit.
The year you arrive or leave: the M-form
For the year in which you moved to or from the Netherlands, you file the M-form (M-biljet, migration return) instead of the normal return. It splits the year into a resident part and a non-resident part and it is longer than the standard form. Since 2025 you can file it online in Mijn Belastingdienst with a DigiD or a European eID. It is published later than the normal return: for tax year 2025 it appeared on 1 May 2026 with a deadline of 1 July 2026. The M-form is where most first-year refunds come from, because a partial year means the payroll withheld tax as if you had worked all twelve months.
Two situations that change the rules
- Short assignments and the 183-day rule. The Netherlands has tax treaties with about 100 countries. For short assignments, the treaty's 183-day rule decides which country taxes the employment income. Long-term residents pay Dutch tax on worldwide income and use the treaty to avoid double taxation.
- Living abroad, working here. Residents of the EU, EEA or Switzerland who earn 90% or more of their income in the Netherlands are "qualifying non-resident taxpayers" and get the same deductions as residents.
Key dates for 2026 and 2027
| Date | What |
|---|---|
| 1 January | Reference date for box 3 and for toeslagen asset tests |
| 1 March | The return for the previous year opens |
| 1 May | Filing deadline (extension to 1 September on request) |
| 31 December | Last day for annuity (lijfrente) deposits and to cancel your health insurer; last day to claim toeslagen for the previous year |
| 31 January | Last day to choose a new health insurer |
Questions people ask
I never got a letter. Do I have to file?
You must file if you expect to owe more than a small threshold. Otherwise it is voluntary, and often worth it. A partial year of employment alone usually produces a refund.
How long does a refund take?
Returns filed before 1 April usually get a provisional assessment before 1 July. Later filings take a few months. The M-form takes longer, often until the end of the year.
Can I do this myself or do I need an adviser?
A standard year with one employer, no property abroad and no business is usually easy to do yourself online. The M-form, a home abroad, a company or two countries of income are the cases where an hour with a tax adviser pays for itself.
Coaching and education, not regulated tax advice. Your assessment from the Belastingdienst is the source of truth for your case.