在西方国家财政承压背景下，针对富人的财富税提案正在扩散。英国、法国、美国多州及加州等地相继提出提高高收入或高净值人群税负的方案，例如对年收入超过100万美元加征2个百分点所得税，或对超过10亿美元净资产一次性征收5%。部分欧洲国家已实施或重新讨论财富税，但目前仅有少数国家保留净财富税。历史数据显示，这类税种往往难以达到预期财政效果，且可能抑制投资并加速资本外流。
跨境与跨州迁移数据凸显了执行难度。挪威对超过约190万克朗的净资产征收1%、超过2,150万克朗征收1.1%的财富税，近期却出现高净值人士外流。美国方面，过去五年约有3万名纽约居民迁往佛罗里达棕榈滩和迈阿密-戴德县，带走约92亿美元收入。欧洲类似趋势明显，英国取消非本土居民税收优惠后，部分富人迁往摩纳哥、迪拜等低税地区。
尽管争议不断，不平等数据为支持者提供依据。美国前10%家庭拥有全国超过三分之二的财富，而在法国、荷兰等国，亿万富翁的有效税率往往低于高收入劳动者。西班牙2024年通过财富税筹集约21亿欧元，瑞士财富税税率约0.1%至0.88%，被视为相对稳定模式。专家普遍认为，若无跨国协调，单边财富税更可能引发税基侵蚀而非显著改善财政状况。
As Western governments face strained balance sheets, proposals to tax the wealthy are proliferating. The UK, France, and several US states are advancing measures such as a 2 percentage point income tax increase on earnings above $1 million or a one-time 5% levy on net worth exceeding $1 billion. Only a handful of European countries still maintain net wealth taxes, and historical evidence shows these taxes often raise less revenue than projected, while potentially deterring investment and accelerating capital flight.
Migration data underscores enforcement challenges. Norway taxes net wealth above about 1.9 million kroner at 1% and above 21.5 million kroner at 1.1%, yet has seen high-profile departures. In the US, roughly 30,000 New Yorkers moved to Palm Beach and Miami-Dade counties over the five years through 2022, taking an estimated $9.2 billion in income. Similar patterns appear in Europe, where changes to tax regimes have pushed affluent residents toward low-tax jurisdictions such as Monaco and Dubai.
Despite controversy, inequality statistics bolster advocates’ arguments. In the US, the top 10% of households own more than two-thirds of total wealth, while in countries like France and the Netherlands, billionaires often face lower effective tax rates than high earners. Spain collected about €2.1 billion from its wealth tax in 2024, and Switzerland’s cantonal rates of roughly 0.1% to 0.88% are viewed as relatively stable. Most analysts conclude that without cross-border coordination, unilateral wealth taxes risk eroding tax bases rather than delivering sustained fiscal relief.