In Brief
- Proposals to tax unrealised gains are advancing in multiple jurisdictions, but none have been fully enacted: the US Billionaire Minimum Income Tax remains a congressional proposal, and the Dutch Box 3 reform has passed only the lower house of parliament, with the Senate yet to vote and the Finance Minister stating that amendments are needed.
- The UAE Corporate Tax Law provides an explicit realization basis election under Article 20, allowing accrual-basis taxpayers to defer recognition of gains until the underlying asset is disposed of — a structural advantage for holding entities in an environment of increasing global mark-to-market pressure.
- The UAE signed the CARF Multilateral Competent Authority Agreement in September 2025; compliance obligations for crypto asset service providers are expected to commence from 1 January 2027, with first data exchanges in 2028. The concept of taxing gains that have not been realised — increases in the value of assets that have not been sold — has moved from academic debate to active legislative proposals in several major jurisdictions.
The political rationale is consistent: high-net-worth individuals hold disproportionate wealth in appreciating assets and can indefinitely defer income recognition by not selling. Proponents argue that annual mark-to-market taxation corrects this deferral advantage. Opponents argue that it creates liquidity problems, is administratively complex, and discourages long-term investment. The practical status of these proposals in March 2026 is mixed. The political momentum that appeared to be building in 2024 has moderated in some jurisdictions and stalled in others. None of the major proposals examined here have been fully enacted. But the direction of travel is clear enough that understanding the UAE's structural position in this global policy environment is a legitimate planning consideration. The US Billionaire Minimum Income Tax: a proposal, not law The Billionaire Minimum Income Tax proposal, most recently reintroduced by Senators Wyden, Cohen, and Beyer in September 2025, would impose a 25% minimum tax on the total income — including unrealised gains — of US households with net worth above $100 million. The proposal targets approximately 700 households and would require annual mark-to-market valuations of non-publicly traded assets. As of March 2026, the proposal has not advanced beyond committee and has no realistic prospect of passage in the current Congress. The political arithmetic in the Senate does not support it, and the Republican-controlled House has not entertained comparable measures. The proposal is relevant as an indicator of the direction that wealth tax advocates are pushing, but treating it as imminent US law would be factually inaccurate. The US exit tax framework under Section 877A of the Internal Revenue Code is, by contrast, existing law. Covered expatriates — US citizens or long-term permanent residents who renounce citizenship or abandon
Disclaimer: This article is for general informational purposes only and does not constitute legal, tax, or financial advice. Readers should seek professional advice tailored to their specific circumstances. Information reflects the position as of the publication date and may be subject to change. This article addresses UAE, Australian, UK, and Canadian law where specified; different rules apply in other jurisdictions. © 2026 Alldren. All rights reserved. This article discusses proposed legislation in the United States and the Netherlands that has not been enacted, and existing UAE tax law. Legislative positions are as of March 2026 and are subject to change. Readers should seek jurisdiction-specific advice before making any structuring decisions.
