How to Correct Your Dutch Tax Return

PublishedMarch 16, 2026

UpdatedMarch 19, 2026

ByJolande Geerts

Short answer

In many cases you can still correct a Dutch income tax return yourself in Mijn Belastingdienst, even after you already submitted it and even after you received a definitive assessment. But the route depends on the stage of the case. A normal correction, a partner-allocation change, a formal objection, an ambtshalve vermindering request and a voluntary disclosure are not the same thing.

For expats, the biggest practical risk is choosing the wrong route too late. So first identify whether the return is still editable, whether there is already an assessment, and whether the issue is an ordinary mistake or undeclared income or assets.

Who this article is for

expats who filed a Dutch tax return and later spotted a mistake
taxpayers who already received an assessment and need to know whether they can still correct the return themselves
people with foreign income, assets or partner-allocation issues who are unsure which correction route still applies

Start with the stage of the case

The most important question is not only what went wrong, but where the file is now. Belastingdienst treats a self-correction in Mijn Belastingdienst differently from an objection against an assessment, and both are different again from a late request for ambtshalve vermindering or a voluntary disclosure.

A practical rule is: first ask whether the return itself is still open for correction, then ask whether you are already in assessment territory, and only after that look at fallback routes.

If you filed the return yourself and spotted a normal mistake

Belastingdienst says you can reopen and change a submitted income tax return in Mijn Belastingdienst. That also applies if you originally used the app, because changes are always made in Mijn Belastingdienst rather than in the app itself.

This is usually the cleanest route for wrong pre-filled data, missing deductions, incomplete foreign-income entries, missing partner data or forgotten explanations. Belastingdienst also says that the last return they receive is the one they process.

If you filed on paper, the practical route is different: submit a new paper form or send a letter with the change, and keep a full copy of what you sent.

Do not miss the special partner-allocation deadline

Belastingdienst makes one exception very clear. The allocation of joint income and deductions with a fiscal partner cannot be changed for the full general correction period. That change is only possible until 6 weeks after the date of both definitive assessments.

So if the problem is not the income itself but the split between partners, move immediately. This deadline is much shorter than the general correction window and catches people by surprise.

If Belastingdienst changed your return first

Sometimes the tax office changes your return and you then want to correct something again. In that situation Belastingdienst says you cannot always simply edit the return yourself. The route can become a verzoek tot herziening instead.

For that request you need to explain why the return is wrong, mention the relevant tax year and send the request to the correct tax office.

If you already have an assessment and the normal objection period is gone

Once you are outside the normal bezwaar period, Belastingdienst says you can still ask for an ambtshalve vermindering if the assessment is too high. The key point is to check the year-specific final date on the official page instead of assuming a generic 5-year rule. Belastingdienst gives explicit dates per tax year.

Belastingdienst also explicitly says that a provisional assessment follows a different route: you cannot use bezwaar or ambtshalve vermindering for a provisional assessment, so you need to change that estimate instead of treating it like a final assessment dispute.

When voluntary disclosure becomes the right route

Voluntary disclosure is not just a late version of an ordinary correction. Belastingdienst presents it as a separate route for people who did not report all of their income or assets, in the Netherlands or abroad, and now want to correct that voluntarily.

That makes it especially relevant in expat cases involving foreign bank accounts, crypto, overseas property, undeclared income streams or earlier years where the original filing was incomplete in a material way.

What to prepare before you submit anything

the tax year, assessment date and whether you are still inside the normal objection period
salary statements, annual statements, mortgage documents and any missing foreign-income or foreign-asset evidence
partner details if the issue affects the allocation of joint income or deductions
a short written explanation of what is wrong, what the correct figures are and which route you think still applies

What to do now

first check whether you can still edit the return directly in Mijn Belastingdienst
if the issue is a partner-allocation change, count the 6-week deadline from both definitive assessments immediately
if the objection period has already passed, check the year-specific ambtshalve deadline on the official page
use the voluntary-disclosure route for undeclared income or assets, not for ordinary filing mistakes

Common mistakes

assuming every mistake must immediately become a bezwaar case
forgetting that partner allocation has a much shorter deadline than the general correction window
treating a provisional assessment like a final assessment dispute
assuming ambtshalve vermindering always follows one simple 5-year formula
using the ordinary correction logic for undeclared foreign income or assets that actually belong in a voluntary-disclosure file

Official sources

Tags:

Tax