The effective tax rate for the wealthiest 0.0002 percent of Americans — a group that corresponds roughly to the billionaires on the famous Forbes 400 list —fell from 30 percent to 24 percent after the 2017 GOP tax cuts, which were extended last month by Congress in Trump’s “big, beautiful bill.”
The effective tax rate for the U.S. population as a whole is about 30 percent, and for people with the top salaries it’s about 45 percent. But for the 100 wealthiest Americans, it’s 22 percent, according to a study published Monday by the National Bureau of Economic Research.
These drop-offs are correlated in the study specifically with the 2017 Trump tax cuts, also known as the Tax Cuts and Jobs Act.
“The tax rate of the top 400 fell significantly at the end of our sample, a period that
includes various economic and policy changes, including the Tax Cuts and Jobs Act,” the researchers note.
The study is by Emmanuel Saez and Gabriel Zucman, economists at the University of California who are two of the foremost experts on global wealth inequality, a trend that has exploded in recent decades.
They noted that while the wealth of the top 0.0002 percent was the equivalent of 2 percent of U.S. gross domestic product (GDP) in 1982, it has hit 20 percent of GDP in 2025, with about three-quarters of the rise being attributable to the top 100 wealthiest individuals alone.
As a fraction of wealth, as opposed to income, taxes paid by the top 400 dropped from 2.7 percent prior to the 2017 tax cuts to 1.3 percent afterwards. The U.S. doesn’t tax people based on wealth, only based on income, though the Supreme Court has recently shown openness to considering a wealth tax.
Surprisingly, the lower tax rates for the super-rich are due in part to a low amount of private business income. Pass-through businesses that generate taxable losses are cited as reducing the tax burdens for the wealthiest Americans, allowing them to offset taxes owed on other income owed on other income sources like wages and dividends.
The centerpiece of the 2017 Trump tax cuts was the reduction of the corporate tax rate from 35 to 21 percent, a change that made a big difference for the billionaire class.
“Out of the top 400’s effective tax rate of 23.8 percent, about 9 points comes from the corporate tax,” Zucman and his coauthors found.
In a distributional analysis of the extension of the 2017 cuts that were signed into law in July, the Congressional Budget Office found that they would shift wealth from America’s poor to the rich. Due to cuts to social programs like health care, the lowest earners would lose resources while the wealthy would gain them.
Those gains increased in the higher portions of the income ladder, with the most gains by far going to the top tenth of earners, mostly in the form of saved tax revenues.
The trend is a global one. While wealth differences between countries have moderated over the last quarter-century, the wealth differences within countries like the U.S. have skyrocketed.
“In 2018, the 26 richest people in the world held as much wealth as half of the global population (the 3.8 billion poorest people), down from 43 people the year before,” the United Nations reported.
Economic historians have considered a new designation for global class structures based on the growing trend of inequality.
“We must also be witnessing the emergence of a new class structure, axed around relations of ‘politically engineered upward redistribution,’” economic historian Robert Brenner and sociologist Dylan Riley wrote in a 2022 paper.
