Introduction
More and more high-tax countries are reluctant to see their tax base leave without a final settlement. As a result, emigrating taxpayers are not only required to file one last (departure) tax return but may also face exit-tax mechanisms. This can take the form of immediate taxation of unrealised capital gains at the moment of departure or a trailing regime under which capital gains become taxable if the assets are sold within a specified period after emigration.
Belgium was traditionally seen as an exception. While individuals leaving Belgium must file a final (exit) tax return covering income earned up to the date of departure, this has never constituted a true exit tax. It merely settles the ordinary income tax due for the period of Belgian residence, without taxing unrealised gains or future income.
That position is now gradually changing. In recent years, Belgium has introduced three different mechanisms that can produce exit-tax-like consequences when a taxpayer leaves the Belgian tax net. What makes this evolution particularly relevant is that some of these rules may lead to taxation without liquidity (through deemed or fictitious events) or even taxation after emigration, via trailing periods that extend Belgium’s taxing reach beyond your departure.
Trailing Capital Gains Tax on Financial Assets
Belgium has moved into a new era this year with the introduction of a capital gains tax on financial assets, and the reform includes an explicit anti-exit mechanism: if you leave Belgium and dispose of certain financial assets shortly afterwards, Belgium may still levy tax during a 24-month trailing window.
The idea is that Belgium wants to tackle situations where someone moves abroad first and sells assets shortly afterwards to escape capital gains tax. Leaving Belgium therefore does not automatically end your Belgian tax exposure.
For example, a private individual moves to Belgium in 2026, holds significant accumulating funds and crypto assets without selling them, and builds a successful business in Belgium during their stay. After leaving Belgium, they sell the company and part of their investment and crypto portfolio sometime later. If these disposals occur too soon after departure, all of these assets may still fall within the scope of the Belgian capital gains tax under the post-departure trailing rules.
Under the new regime, the moment of departure becomes the decisive reference point for determining the taxable capital gain, even if the actual disposal occurs at a later date. Whether Belgium can ultimately tax that gain will still depend on the applicable double tax treaty, as most treaties allocate taxing rights on capital gains to the country of residence at the time of sale. Belgium will likely argue that the taxable event occurs immediately before departure, to preserve its taxing rights.
A move to an EU/EEA country or to a country with a qualifying tax treaty results in an automatic deferral of exit-tax payment, whereas relocation to a third country requires the taxpayer to provide a guarantee to secure payment of the exit tax. The Belgian Finance Minister has recently clarified that this group notably includes Monaco and the UAE, and—more strikingly—even Switzerland, due to the absence of a tax recovery assistance clause in the applicable tax treaty.
Emigration planning is therefore increasingly about timing. What you sell, when you sell it, and which tax treaty applies can be just as important as the move itself.
Corporate Relocation Exit Tax: Extended to Shareholders
Belgium has long had a corporate exit tax when a Belgian company effectively emigrates (for example, by transferring its registered address abroad): unrealised gains can be treated as realised. As a result, the emigration of a Belgian company to another country is for tax purposes treated in the same way as a liquidation of the company.
What changed in 2025 is that the Belgian legislator added a second layer: shareholders can now be taxed as well, through a deemed (fictitious) liquidation dividend, even if no money is distributed to them. The tax must in that case be paid out of pocket.
In practice, the tax impact depends on the nature of the shareholder. For individual shareholders, the fictitious dividend is generally taxed in the same way as a regular dividend, often at a rate of 30%, subject to possible reductions depending on the applicable regime and the specific facts. Corporate shareholders may benefit from relief under the participation exemption rules, provided the relevant conditions are met. In addition, the emigrating company has a formal compliance role and must issue the required shareholder tax documentation; failure to do so can result in severe penalties.
A crucial point to bear in mind is that moving the company abroad is not the same as the shareholder moving personally; only the former will trigger this specific deemed dividend taxation at shareholder level. In Belgium, exit tax risk now depends heavily on what is exiting: the company’s seat, the shareholder’s residence, or both.
Finally, the risk of double taxation in this case is very real. If the country of arrival does not recognise the deemed dividend, it may also refuse to grant an exemption or tax credit for tax already paid in Belgium when the income is later actually distributed. This can lead to an odd outcome: a shareholder who liquidates a Belgian company instead of relocating it could end up in a more favourable tax position.
Cayman Tax: Exit Tax Consequences for Founders
The third one is the most technical: the Belgian Cayman tax regime (targeting trusts, life insurance policies and certain low-taxed “legal constructions”) now explicitly includes an exit-tax element upon emigration of the founder.
For example, a U.S. citizen who moves to Belgium for a few years and who is the founder of a U.S. trust and/or a U.S. LLC which may be treated as a “legal construction” under the Belgian Cayman tax rules. If that individual later leaves Belgium, the Cayman tax regime can treat the undistributed income of the foreign structure as deemed distributed at the time of departure, triggering Belgian taxation without any actual payout.
In broad terms, Belgium can treat undistributed amounts as deemed distributed when the founder leaves Belgium, bringing latent income into charge at the point Belgium loses its grip. And unlike a normal dividend tax, the liability can arise in a “paper” scenario where no cash comes out of the structure.
However, a recent intervention of the Belgian Constitutional Court introduced some important nuances in this respect. In particular, the exit tax may only relate to income that was reserved during the period of Belgian tax residence of the founder. Moreover, the Court also clarified that the notion of “undistributed income” refers exclusively to reserved profits, and does not extend to latent (unrealised) capital gains.
If a client has a Cayman-tax-relevant structure, emigration is no longer just a residence issue; it can become a deemed distribution / exit taxation event in itself.
Conclusion
Belgium is effectively building an exit-tax framework through different channels:
- 1. a 24-month trailing mechanism linked to the new capital gains tax (from 2026 onwards),
- 2. a shareholder deemed dividend when a Belgian company migrates abroad (relevant since July 2025),
- 3. a Cayman tax emigration trigger for founders of trusts and certain legal constructions (highlighted since 2025).
The common thread is that these rules can lead to taxation without liquidity or taxation after the move, rather than at the moment value is actually realised. In more complex cases, the effects may also overlap, for example where a shareholder relocates, a company migrates, and a foreign legal structure is involved. How these different exit taxes will ultimately interact remains uncertain and may, over time, be challenged before the tax courts. Taken together, these new exit tax rules add an additional layer of complexity to any planned exit from Belgium.