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2026 California Billionaire Tax Act

Constitutional Flaws of California’s Proposed Wealth Tax

The California Billionaire Tax Act (Proposition 40), which imposes a one-time 5 percent tax on billionaires’ net worth, is vulnerable to numerous constitutional challenges, any of which could invalidate the tax in whole or in part.

28 min read

The Five Most Pro-Growth Options in the Options Guide

Some taxes have more powerful economic effects than others, and that’s a lesson policymakers should absorb as they work to craft a tax code that encourages growth and raises sustainable revenue.

8 min read
Wealth Taxes, Government Revenue

Why Wealth Taxes Always Fail

Though they are often framed as affecting only the richest households, the economic effects of wealth taxes extend much further by reducing capital formation, discouraging entrepreneurship, curtailing wage and employment growth, and ultimately weakening the overall economy.

Wealth Taxes in Europe, 2026

Wealth Taxes in Europe, 2026

Wealth taxes not only collect little revenue and create legal uncertainty, but an OECD report argues that they can also disincentivize entrepreneurship, harming innovation and long-term growth.

5 min read
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Wealth Taxes, Government Revenue

Why Wealth Taxes Always Fail

Though they are often framed as affecting only the richest households, the economic effects of wealth taxes extend much further by reducing capital formation, discouraging entrepreneurship, curtailing wage and employment growth, and ultimately weakening the overall economy.

The California Billionaire Tax Act

Why Billionaires Are Still Leaving California

The California Billionaire Tax Act’s residency provisions are exceptionally vulnerable to legal challenge. Even if the tax passes and survives challenges to its broader constitutionality, billionaires who leave California sometime in 2026 have good reason to believe they can escape some or all of the tax.

Ded Pixto, AdobeStock

A Taxing Approach to High Energy Costs Will Backfire

If you want more energy production, taxing producers is the wrong place to start. And if you want to tax companies more if they’re making big profits, the corporate income tax already does that.

US-Mexico-Canada-Agreement (USMCA), Trump Trade Policy

USMCA Is Up For Review. The US Would Be Foolish Not to Extend It

President Donald Trump has decided against a clean extension of the US-Mexico-Canada Agreement (USMCA), allowing the bloc of countries to enter a prolonged period of annual reviews, renegotiations, and, possibly, a shift to bilateral deals.

Tax Education - girl in classroom

TaxEDU is designed to advance tax policy education, discussion, and understanding in classrooms, living rooms, and government chambers. It combines the best aspects of cutting-edge and traditional education to elevate the debate, enable deeper understanding, and achieve principled policy.

TaxEDU gives teachers the tools to make students better citizens, taxpayers a vocabulary to see through the rhetoric, lawmakers crash courses to write smarter laws, and videos and podcasts for anyone who wants to boost their tax knowledge on the go.

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  • Glossary

    Understand the terms of the debate with our comprehensive glossary, including over 100 tax terms and concepts.

  • Videos

    Our animated explainer videos are designed for the classroom, social media, and anyone looking to boost their tax knowledge on the go.

  • Primers

    Our primers are classroom-ready resources for understanding key concepts in tax policy.

  • Lessons

    Dive deeper into specific tax topics with lesson modules designed as a classroom-ready resource or for anyone looking to boost their tax knowledge.

  • Principles

    Learn about the principles of sound tax policy—simplicity, transparency, neutrality, and stability—which should serve as touchstones for policymakers and taxpayers everywhere.

  • Courses

    Our Tax Foundation University and State Tax Policy Boot Camp lecture series are designed to educate tomorrow's leaders on the principles of sound tax policy.