Billionaires like Jeff Bezos and Mark Zuckerberg spend six figures a year maintaining their superyachts. Here's how.

• Superyachts are one of the most expensive assets money can buy.
• The true cost of ownership is even more, adding up to millions a year.
• Here's how much it costs to own a superyacht — and what that money is going toward.

Financial advisors are quick to warn prospective owners that a boat is nothing more than a hole in the water in which to throw money. When it comes to superyachts, you'd better have bags and bags of cash.

As one luxury agent told Business Insider at the Palm Beach International Boat Show: "Buying a boat, it's a huge purchase — and nobody needs a yacht."

A superyacht, generally over 30 meters long, is one of the most expensive assets money can buy, with the largest costing more than a lot of real estate or a private jet. Billionaires like Jeff Bezos, Mark Zuckerberg, and Steve Jobs each spent nine figures on their megayachts.

That doesn't include operating costs. Owners should expect to pay about 10% of a yacht's new-build price each year, experts told Business Insider. That's tens of millions of dollars annually for the most luxurious boats.

"It's a small-to-medium-sized business in its own right," said Jeffrey Beneville, a senior vice president at insurance company NFP, where he specializes in consulting clients about yachts.

Unlike many smaller boats, superyachts need staff, not just a captain. Some superyachts have space for dozens of crewmembers, including a chef, engineer, and masseuse for the guests onboard. Each gets an annual salary — the highest-ranking members earn six figures — and benefits. Eric Schmidt's yacht fits a crew of 28 for a ratio of about two crewmembers per guest.

Then there's fuel, dockage fees, routine maintenance, and insurance. The latter hinges on everything from the reputation of a yacht's shipyard to where an owner wants to take it (if a vessel is taking frequent trips to the South China Sea, for example, expect to pay a higher premium). If a superyacht has a support yacht — or a support superyacht, in Bezos' case — expect to pay another 10% of that boat's price annually.

"The cost to maintain a yacht is so high that they just think that money's getting lit on fire," Matthew Fleissig, the CEO of wealth management firm Pathstone, told BI of his clients who choose to charter rather than own.

One of his firm's clients who does own has a 23-meter yacht valued at $5.2 million. The annual cost to staff, maintain, dock, and insure the boat is $346,297, according to documentation provided to BI. The lion's share is spent on marina fees ($95,970) and maintenance work ($88,408.) While not exactly a Sunfish, that boat is too small to count as a superyacht.

At 106 meters, the Amadea, owned by a sanctioned Russian oligarch, definitely does. The $300 million yacht, which was seized in 2022 and is docked in San Diego, cost $922,000 a month to maintain, a court filing showed: $360,000 for crew salaries, $75,000 for fuel, $144,000 for insurance, $178,000 in dry-docking fees, and $165,000 for maintenance, waste removal, food for the crew, and miscellaneous expenses.

"And that's an inactive yacht that's in the water," NFP's Beneville said.

If it were operational and carrying guests, the costs would be about twice that, or between $20 million and $30 million a year, he added.

Of course, it makes more financial sense for the non-obsessives to charter, and many of Fleissig's clients do. And some owners choose to offer their yachts for charter — the most luxurious cost as much as $1 million a week — to offset the costs.

"If you charter the boat for 50 days a year, it's going to help a lot," Anders Kurtén, the CEO of brokerage firm Fraser Yachts, told BI.

Then again, the running costs don't matter as much at a certain point. "If you're worth $30 billion, it's nothing. And if you're worth $117 billion — and these are the guys we're talking about — they're in it as long as it's still enjoyable for them," Beneville said. "It's not a money thing."