End of year tax checklist

What's on your end of year tax checklist?

Two things. One is the documents your 2026 Dutch tax return needs. Most are ready in January. The other is a short list of year-end actions you may want to consider. Their dates come sooner. Most only have an effect if you complete them before 31 December 2026. Three take effect on 1 January 2027 instead. That date determines your Box 3 position, or your benefit eligibility for 2027. Box 3 is the Dutch tax on your savings and investments.

This page covers both in one place. The deadline table shows each action and its date. The text around it links to the TaxSavers guides that explain the exact figures. The documents table shows each category and where you find it. A linked figure might be a mortgage rate, an annual margin or a Box 3 threshold. Those guides keep the figures current, so we don't repeat them here.

Who this checklist is for.

This checklist is for internationals filing a Dutch tax return. Every item below applies to a specific situation, not to everyone at once. Take one reader as an example. Daniel moved to Amsterdam two years ago for a Dutch employer. He bought a small apartment with a mortgage, and still holds an old workplace pension pot in the UK. He has also lived with his Dutch partner for over a year. They met the fiscal-partnership condition in November. He needs some of the documents below, and three of the deadline actions. You'll likely recognise your own situation in a few of the items too, even if your mix looks different from his.

Which documents do you need to gather?

Ten categories cover almost every Dutch tax return. Daniel needs six of them this year. He needs his BSN, his DigiD and his employer's jaaropgave (annual income statement). He also needs his mortgage statement, his WOZ-waarde, and his Dutch bank overview. The table below covers all ten. It explains why the Belastingdienst wants each one, and where you actually find it. Working as a freelancer or business owner? Your business records apply on top. Our guide for freelancers and business owners covers those extra records.⁴

BSN and DigiD are not the same thing.

Your BSN identifies you to the Belastingdienst. DigiD is the separate login that lets you act on that identity online. You need both to file.

What do you need to do around year-end?

A handful of actions, each tied to a date. Miss your own date, and the opportunity resets for another twelve months. Three of these apply to Daniel: fiscal partnership, a pension-gap check, and mortgage-interest prepayment. Check the 1 January figures in our rent-allowance and Box 3 and assets guides.

Should you prepay mortgage interest before 31 December?

Only if you expect a lower interest rate or a smaller mortgage next year. Prepaying moves part of next year's deductible interest into this tax year. A mortgage advisor can run the actual numbers for your situation. Our mortgage-advice guide covers how that check works.

When does fiscal partnership need to be in place?

Before the calendar year ends, if you want that full year to count. The Belastingdienst looks at whether you met a qualifying condition during that specific year.³ Most often that's a notarial cohabitation agreement, a shared child, or joint home ownership. Daniel and his partner met the condition in November, so this tax year already counts for them. Sign it in January instead, and only next year counts. Our tax-partner allocation guide covers what fiscal partnership changes for your return. You can't apply for fiscal partnership. It applies once you share a registered address and meet a condition.

How do you check a pension-gap or annuity top-up before year-end?

You compare your annual margin, called jaarruimte, against what you've already paid in. Daniel's Dutch pension started two years ago, so his unused margin comes from those two Dutch years. A deposit into a lijfrente account before 31 December is deductible in this tax year. A deposit made in January only counts in next year's return. Our pension gap and annuity guide covers how to work out your own jaarruimte.

Daniel's checklist in practice.

Daniel started in December with his three deadline actions. They needed more thought than the paperwork. Fiscal partnership needed nothing extra: he and his partner already met the condition in November, so this tax year counts for both of them. The pension-gap check needed a call with an advisor. The advisor worked out his unused jaarruimte from his two Dutch pension years. A modest lijfrente deposit before 31 December, he learned, would lower this year's taxable income. Mortgage-interest prepayment, he decided against, since his current rate is already lower than what he'd expect next year. His documents followed in January and took an afternoon. His BSN and DigiD were already active. His employer's jaaropgave arrived by email, and his mortgage lender's portal had the jaaropgaaf ready by mid-January.

What does this mean for you?

Start with the deadline-action table, because its dates fall before the January documents. Check it against your own situation. If you own a home, check mortgage-interest prepayment. If you live with a partner but aren't married, check fiscal partnership. If you have a pension from more than one employer or country, check your pension gap. Each one has its own date, so check that date before you act. Then gather your documents in January, most of them at once. You usually need to file before 1 May, unless you request an extension. If you arrived or left the Netherlands this year, ask about the M-form. Do you still have the 30 percent ruling and did you use it before 2024? For 2026 you can then still choose partial non-resident status. That keeps your foreign savings and investments out of Box 3. A foreign pension pot may need its own document too. A short conversation now is worth more than a longer one in April.

You can see how we handle a full return on our page about help with your tax return.