Europe's 2026 Reversal Wave: Sweden Debates Reinstalling What It Deleted, and the UK's Non-Dom Exodus Gets a Number
Two European developments this month sharpen the feasibility record on both sides of the ledger.
Sweden: the reinstatement debate — and the data problem repeal created. With Sweden's election campaign underway, the Green Party and Left Party are proposing a tax on individuals with assets exceeding 1 billion crowns (~€94M) that "could raise up to 50,000 million crowns annually" — a figure that "is disputed and SVT has warned that there is a high uncertainty about the actual revenue that would be obtained" (Demócrata). The historical record that frames the debate: the Tax Agency had estimated ~500 billion crowns placed outside the country to avoid the old tax when Reinfeldt's government repealed it effective January 1, 2007, forgoing ~6.9 billion crowns a year. But the most instructive finding is administrability in reverse: "Sweden no longer maintains a complete tax register of wealth since the tax disappeared in 2007. This makes it difficult to know exactly how many people would exceed certain thresholds and how much a potential new tax figure could collect.1 The Green Party itself acknowledges this limitation." That is a first-order lesson for the US debate — repealing a wealth tax (or never enacting one) destroys the data infrastructure needed to score and administer a future one; the Green Party's own 50B-crowns/yr claim rests on estimates made without the register the old tax's repeal eliminated. Social Democratic leader Magdalena Andersson has ruled out reviving the general wealth tax ("It is not something we propose"), preferring bank/ISK/income-based measures — while Spotify co-founder Martin Lorentzon has warned he could leave if it returns, and the neighboring Norwegian flight record (NBER's Norway Verdict (2021–2025): Flight Is Real but Cost Only ~3.5 Points of a 75% Revenue Gain) looms over both sides' arguments. Note Sweden still taxes capital: the ISK account regime's effective rate is 1.065% on taxable capital for 2026 — the debate is over taxing unrealized stock, not over billionaires going untaxed.
The UK: a mobility number with a built-in caveat. A Bloomberg Billionaires Index analysis finds "super-rich UK residents worth a combined £121bn have either left or loosened ties with UK since the Labour government came to power in 2024. This represents more than half of all billionaire wealth" (The Guardian, Oct 7). The exits (Mittal, Sawiris, Fredriksen, now David Reuben to Monaco) are blamed on Rachel Reeves' abolition of the non-dom regime plus feared inheritance-tax changes. CenTax director Arun Advani supplies the skeptical read: "Mobility among billionaires is high. Many wealthy people leave every year, it just isn't always reported as loudly as at the moment. So a couple of highly reported examples don't in themselves indicate anything has changed." Two methodological flags for the capital-flight file: (1) the UK changed the income-tax base for foreign residents, not a wealth tax — this is evidence on high-earner mobility, not wealth-tax administration per se; (2) flows go both ways — crypto billionaires Christopher Harborne and Ben Delo recently registered as UK residents. The relevant lesson for the US debate is about the margin of response at the very top: when a headline tax treatment changes, the most mobile cohort moves first and loudly, and both the magnitude and the counterfactual are contested.
The reversal wave is real but running in both directions: Hungary is formally proposing a new wealth tax (Hungary's Wealth Tax Is Now on Paper: 1%/1.5% Tiers, HUF 800B Over Four Years, First Declarations August 2027), Sweden is debating reinstatement, while the Netherlands' mark-to-market retreat (The Netherlands Retreats From Taxing Unrealized Gains: A Mark-to-Market Administrability Case Study) shows even high-capacity administrators walking back unrealized-gains taxation. The empirical question — does the flight response overwhelm the revenue — is now being answered with actual numbers on both sides (Ring's 75%→71.5% for Norway; £121B headline vs. Advani's base-rate objection for the UK).
-
An instance of Repealing a wealth tax deletes the machinery needed to score or collect the next one. — Repeal erased the register that scoring and administering any reinstated tax requires, so even the Green Party's own revenue estimate rests on data that no longer exists. ↩︎