Billionaires Elon Musk and Mark Zuckerberg used mortgages to buy multimillion-dollar mansions. Here’s why that’s a savvy financial decision

Even the world’s most affluent people sometimes need a mortgage.

Elon Musk is the world’s richest man, on track to become the first-ever trillionaire, but he’s done one thing most average Americans have to do: take out a mortgage. 

The Tesla CEO has taken out several mega mortgages, including $61 million from Morgan Stanley, on five properties in California, according to the Los Angeles Times. That’s barely a drop in the bucket of his now $662 billion net worth, so it could be difficult to understand why he’d borrow tens of millions of dollars to buy real estate. 

But financial experts say taking out a mortgage—even when you could easily pay cash—can actually be a smart wealth strategy.

Why wealthy buyers still take out mortgages

One of the main reasons is that most of the wealth held by UHNW people is tied up in investments, stocks, and bonds, and they don’t keep as much liquid cash on hand. 

“Ultrahigh-net-worth individuals think differently about liquidity and leverage,” Miltiadis Kastanis, executive director of sales at Compass, told Fortune. “They’d rather keep their money working for them in investments, businesses—or even art—rather than tying it all up in one property.”

Meta CEO Mark Zuckerberg, the world’s fifth-richest man, has also used mortgages to his advantage. In 2012, Zuckerberg refinanced his Palo Alto home with a 30-year, 1.05% adjustable-rate mortgage, according to CNBC. With such a low rate, the mortgage cost him practically nothing, so it didn’t make sense to have nearly $6 million tied up in a home. Plus, borrowing during the era of ultralow interest rates in the 2010s was especially attractive. Many wealthy buyers locked in mortgages at a much lower rate than today.

“If they believe their investments will yield a greater return than the interest they’re paying on a mortgage, it makes more sense to finance the property,” Kastanis added. “It’s less about the cost of the loan itself and more about optimizing where their money is placed.”

Mortgage interest can also be tax deductible on loans up to $750,000 for those who itemize when filing their taxes. While Zuckerberg’s mortgage was more than that, he can likely deduct at least part of his mortgage interest, which further reduces borrowing costs. 

“Mortgages also allow for tax optimization in some jurisdictions, as interest payments may be deductible,” Islay Robinson, founder and CEO of mortgage brokerage Enness Global, told Fortune. “And in high-inflation environments, the value of money erodes over time, making it advantageous to borrow now and repay later.”

Celebrities use the same strategy

Many celebrities and wealthy buyers take the same approach.

Take Paris Hilton, who took out a mortgage on the $63 million mansion she bought from Mark Wahlberg in Beverly Hills. Hilton is estimated to be worth between $300 million and $400 million. 

What’s even more interesting is that she and her husband, Carter Reum, reportedly took out the loan after they had already bought the 12-bed, 20-bath home, which shows a $43.75 million mortgage with JPMorgan Chase at an interest rate of 5.25%.

“It surprises many people, but it’s actually quite common for the mega-wealthy to take out mortgages—even when they could write a check for the full purchase price,” Evan Harlow, real estate agent at Maui Elite Property, previously told Fortune. 

Tax and inflation advantages

Another reason ultrawealthy buyers borrow rather than pay cash is that they often take out loans backed by their investment portfolios. Known as securities-based lending, these loans allow clients to borrow against stocks or other assets without selling them and triggering capital gains taxes. Large banks often promote these types of loans to wealthy clients.

“Rather than selling your public market investments to raise money, borrowing against your assets can allow you to stay the course on your investments, defer taxes, and free up money for other opportunities,” according to J.P. Morgan. “It’s a way to tap into the value of what you own while keeping your financial plans intact.”

Because borrowed money is not treated as taxable income under U.S. law, wealthy individuals can finance spending by taking loans against their assets without triggering income taxes. Analysts often describe the practice as “buy, borrow, die”: accumulate appreciating investments, borrow against them to fund consumption, and ultimately pass those assets to heirs with a stepped-up basis that largely eliminates the accumulated capital gains tax.

What everyday buyers can learn

For billionaires and everyday buyers alike, the decision ultimately comes down to how they want their money working—locked into a house, or invested elsewhere.

Is it better to lock it into a house—or invest elsewhere?

“The takeaway for the average buyer isn’t to mimic their precise approach, but to understand the principle,” Harlow said. “Sometimes the smartest financial move isn’t paying everything off, but keeping your money flexible and working for you.”

This story was originally featured on Fortune.com