Dutch lawmakers have backed a major rewrite of the Box 3 tax, the part of the Dutch personal income tax that covers savings and investments. The bill is called the “Actual Return in Box 3 Act” (in Dutch: “Wet werkelijk rendement box 3”). If the Dutch Senate approves it, the Box 3 tax will switch on January 1, 2028, with a flat 36% rate on what the government defines as an investor’s actual return.
The change follows years of legal pressure. In December 2021, the Dutch Supreme Court ruled that the old Box 3 tax system could violate basic rights under the European Convention on Human Rights because it taxed people on assumed returns they did not earn. Later rulings kept that pressure on the government. With the court rejecting fixes, lawmakers faced a problem: the state still needed a legal way to charge the Box 3 tax and protect the budget.
The new plan tries to solve that by taxing actual results instead of a made-up formula. Under the updated Box 3 tax, “actual return” includes cash income like interest, dividends, and rent. It also includes changes in value during the year for many assets, even if the owner does not sell. That means the Box 3 tax can apply to “unrealized gains,” also called paper gains. If someone owns shares that rise by €10,000 in a year, the Box 3 tax would treat that €10,000 increase as taxable income, even if the shares stay in the account.
This is where the debate gets sharp, especially for people who own crypto. Crypto prices can jump or drop fast. A person could face a large Box 3 tax bill after a strong year, even if they never converted any crypto to euros. Critics say that creates a liquidity risk: the Box 3 tax can demand cash when the gain is not cash. Supporters answer that the state needs a workable system and that the law adds tools to soften the impact.
One big softener is a new tax-free rule. The reform removes the old tax-free asset threshold and replaces it with a tax-free annual return of €1,800 across all Box 3 tax assets. If total actual return stays below €1,800, no Box 3 tax is due. The bill also adds an unlimited loss carryforward. If an investor has a net loss in one year, they can carry it forward and use it to reduce taxable gains in future years, with no time limit. Only losses above €500 qualify; smaller losses get written off. Lawmakers say these features make the Box 3 tax less harsh for small savers and help investors recover after downturns.
The bill also treats some assets differently. For real estate and shares in qualifying startups, the government chose a capital gains approach for value increases. Under that approach, the Box 3 tax on the appreciation of value is charged when the asset is sold or disposed of, not every year. But regular income from those assets, like rent or dividends, still faces the Box 3 tax in the year it is received. The government said it picked this split approach in part because of the same liquidity risk critics raise: it can be hard to pay the Box 3 tax every year on assets that do not produce steady cash.
The reform sits inside a wider system that divides personal income into three “boxes.” Box 1 covers wages and home ownership rules, with progressive rates. Box 2 covers “substantial interest,” meaning at least 5% ownership in a company, with its own rate structure. Box 3 tax is the piece now set for the largest redesign, and it matters to anyone holding savings, stocks, bonds, funds, or crypto as a resident.
Crypto exposure is one reason the Box 3 tax debate draws attention beyond tax experts. De Nederlandsche Bank (the Dutch central bank) reported that indirect crypto investments held by Dutch companies, institutions, and households reached about €1.2 billion by the end of October 2025, up from €81 million at the end of 2020. It also reported the financial sector held €113 million in direct crypto holdings at the end of the third quarter of 2025. Even with that growth, the central bank said crypto securities remain a small slice of the wider Dutch securities market.
Lawmakers also approved an amendment to shorten the law’s review period from five years to three. The goal is to allow faster changes if the Box 3 tax rollout causes problems once it begins. Several parties that supported the bill have said they do not love the idea of taxing unrealized gains. Still, they argue that after court rulings, the government needs a legal framework, and delays add budget strain.
For now, the plan is not final. The Dutch Senate still must vote. If senators approve, residents and advisers will have about two years to prepare for a Box 3 tax that shifts from assumed results to actual return, and that may tax paper gains for many common assets.
