First Dutch Tax Return (M Form)

The tax return for the year you moved, why it often means money back, and how to file it without paying someone a fortune.

Who this is for

Filipino devs who moved to the Netherlands partway through a year and are now hearing colleagues talk about “doing their taxes” while you have no idea if that applies to you. It does, and for the year you migrated there is a special version: the M form (M for migration).

What this helps you decide or do

Your payslip tax was withheld as if you would earn your Dutch salary for the whole year. If you landed in, say, August, you only earned it for part of the year, so the withholding was often too high. The M form is how the Belastingdienst recalculates your migration year, and for many first-year migrants that ends in a refund. This page tells you what the M form is, when and how to file it, and what to have ready. It is not tax advice, and your numbers are your own, so verify anything specific with the Belastingdienst or a tax adviser.

Quick checklist

1. Know which year needs the M form: the calendar year you moved to the Netherlands. Every normal year after that uses the standard return.
2. You file it online in Mijn Belastingdienst with your DigiD. The online form for your migration year opens on 1 May of the following year, so if you land in August 2026, your M form moment is from May 2027. Put it in your calendar now, because by then it will feel like ancient history.
3. If the Belastingdienst sends you a letter telling you to file (aangiftebrief), take the deadline in that letter seriously, and ask for an extension before the deadline if you need one.
4. No letter does not mean no refund. If you are not invited to file, you can still file voluntarily, and you can generally go back up to 5 years. If you moved in a previous year and never filed an M form, it may still be worth doing.
5. Gather the small pile you need before you start: your jaaropgave (annual income statement from your employer, arrives early in the new year), your BSN, your Dutch bank account number (IBAN), and the date you registered in the Netherlands. If the 30% ruling applies to you, your payroll already reflects it, so have that paperwork handy too.
6. Declare honestly for the part of the year before you moved. The form asks about your situation in both countries for the migration year. Answer what is true, and if your PH-side situation was complicated (property, business income), that is the point where a tax adviser earns their fee.
7. Expect the wait. M forms are often reviewed more manually than standard returns, so the refund can take months. Filing early does not always mean fast, it just means done.
8. Do the math before paying for help. Plenty of expat tax firms will file an M form for a fee. For a straightforward case (one employer, no assets, arrived and worked), many people manage the online form themselves. If your case has layers, paying a professional once for the migration year can be worth it.
9. Keep a copy of what you filed and the final assessment (aanslag). Future admin (mortgage, allowances, the next return) is easier when the first year is documented.

Common mistakes

• Assuming taxes are fully handled because your employer withholds every month. Withholding is an estimate. The return is the settlement, and in a migration year the estimate is often off in your favor.
• Missing the moment entirely because nobody told you the migration year has its own form. Colleagues who have been here for years file a different return and will not think to warn you.
• Ignoring a Belastingdienst letter because it is in Dutch. Letters from them are never decorative. Translate it, then act on it.
• Paying a premium fee for a simple case, or the reverse: fumbling a complicated case solo to save money. Match the help to the case.
• Forgetting the refund is not instant, then panicking about whether the filing worked. Slow is normal for M forms.

What to verify

• Whether and when you need to file, and your exact deadline, with the Belastingdienst (their letter or their tax line).
• Your own numbers with the actual form and your jaaropgave, not with anyone’s estimate, including this page.
• Anything involving the 30% ruling, PH-side income, or property, with a qualified tax adviser.

Jake note

The migration-year return is one of those tasks that looks scarier than it is: a long form, in Dutch tax language, about the most chaotic year of your life. The thing I want you to keep from this page is simple. A partial year of Dutch work usually means the payroll tax assumed a full year, and the only way that difference comes back to you is if you file. Set the reminder for May of the year after you land. It is one of the few pieces of Dutch admin that can end with money moving toward you.