For regular people, borrowing money is often something done out of necessity, say for a car or a home. But for the ultrawealthy, it can be a way to access billions without producing income, and thus, income tax.

The tax math provides a clear incentive for this. If you own a company and take a huge salary, you’ll pay 37% in income tax on the bulk of it. Sell stock and you’ll pay 20% in capital gains tax — and lose some control over your company. But take out a loan, and these days you’ll pay a single-digit interest rate and no tax; since loans must be paid back, the IRS doesn’t consider them income. Banks typically require collateral, but the wealthy have plenty of that.

The vast majority of the ultrawealthy’s loans do not appear in the tax records obtained by ProPublica since they are generally not disclosed to the IRS. But occasionally, the loans are disclosed in securities filings. In 2014, for example, Oracle revealed that its CEO, Ellison, had a credit line secured by about $10 billion of his shares.

Last year Tesla reported that Musk had pledged some 92 million shares, which were worth about $57.7 billion as of May 29, 2021, as collateral for personal loans. Elon Musk Tesla Inc. 2014–2018 Wealth Growth: $13.9B Total Income Reported: $1.52B (10.94% of wealth) Total Taxes Paid: $455M (3.27% of wealth)

With the exception of one year when he exercised more than a billion dollars in stock options, Musk’s tax bills in no way reflect the fortune he has at his disposal. In 2015, he paid $68,000 in federal income tax. In 2017, it was $65,000, and in 2018 he paid no federal income tax. Between 2014 and 2018, he had a true tax rate of 3.27%.

The IRS records provide glimpses of other massive loans. In both 2016 and 2017, investor Carl Icahn, who ranks as the 40th-wealthiest American on the Forbes list, paid no federal income taxes despite reporting a total of $544 million in adjusted gross income (which the IRS defines as earnings minus items like student loan interest payments or alimony). Icahn had an outstanding loan of $1.2 billion with Bank of America among other loans, according to the IRS data. It was technically a mortgage because it was secured, at least in part, by Manhattan penthouse apartments and other properties.