The Tax System Is Progressive

At Pew, Drew DeSilver confirms that the US tax system is progressive:

In 2014, people with adjusted gross income, or AGI, above $250,000 paid just over half (51.6%) of all individual income taxes, though they accounted for only 2.7% of all returns filed, according to our analysis of preliminary IRS data. Their average tax rate (total taxes paid divided by cumulative AGI) was 25.7%. By contrast, people with incomes of less than $50,000 accounted for 62.3% of all individual returns filed, but they paid just 5.7% of total taxes. Their average tax rate was 4.3%.

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All but the top-earning 20% of American families pay more in payroll taxes than in federal income taxes, according to a Treasury Department analysis.

Still, that analysis confirms that, after all federal taxes are factored in, the U.S. tax system as a whole is progressive. The top 0.1% of families pay the equivalent of 39.2% and the bottom 20% have negative tax rates (that is, they get more money back from the government in the form of refundable tax credits than they pay in taxes).