Over the years, it has gotten more expensive to both throw and to attend a wedding. Today’s average U.S. wedding costs over $25,000, with couples on average spending between $19,000 and $32,000.

But some of the America’s richest couples understand that the perfect wedding doesn’t need to break the bank — it doesn’t even need to be fancy.

With wedding season fast approaching, here are four millionaire and billionaire couples that prove having a low-key wedding is worth it.

Berkshire Hathaway CEO Warren Buffett, who says marriage “is the most important decision that you make,” got married to his longtime friend Astrid Menks in 2006, after his first wife of nearly three decades, Susan Buffett, passed away in 2004.

“Who you marry, which is the ultimate partnership, is enormously important in determining the happiness in your life and your success and I was lucky in that respect,” Buffett tells Forbes.

Buffett, dressed in his business suit, and Menks, wearing a silk top and white pants, held a small wedding ceremony at Buffett’s daughter Susie’s house in Omaha, Nebraska. Buffett’s sons were out of the country, so the only other people there were Susie, Menks’ sister and the judge who officiated during the 15-minute-long ceremony.

Their cozy, post-wedding dinner party took place at Regency’s Bonefish Grill, a casual seafood restaurant not far from the house.

Even before ABC’s “Shark Tank” investor and personal finance authorKevin O’Leary became rich, he had his eye on the prize. He forewent an elaborate wedding for something more affordable: a big pizza party.

“I said to my wife, ‘Why go in debt?’ Let’s invite our friends over, let’s buy a few cases of beer and I’ll order some pizza,'” O’Leary tells CNBC Make It.

He has also endorsed the concept of casual weddings on Twitter.

Tweet

O’Leary and his bride used the money to support his entrepreneurial aspirations instead. “We saved a fortune,” O’Leary says. “I was able to put it in my business to start growing it.”

“Priscilla and I wanted a low-key wedding so we decided to make it a surprise and have it in our backyard. I sent our friends and family an email telling them I was throwing a surprise party for Priscilla to celebrate her graduation from medical school,” Facebook CEO Mark Zuckeberg wrote in a post celebrating his fifth anniversary with Priscilla Chan last year.

“Since they thought it was a surprise for Priscilla, they kept it quiet. When they showed up at our home, I told them we were getting married. It was a great day,” he said.

A day after Facebook went public in 2012, the two college sweetheartsgot married in the backyard of their $7 million Palo Alto, Calif., home. There were reportedly fewer than 100 guests present.

For dinner, the couple served up Mexican food and sushi catered from local restaurants. For dessert, guests got chocolate mice, worth $3.50 each, from a local chocolate maker.

Steve Jobs was called “one of America’s most eligible bachelors” by Newsweek in 1991 ahead of his marriage to Laurene Powell. Though not much is known about the couple’s wedding, they reportedly kept things simple.

The two got married on March 18, 1991, in “an intimate Zen Buddhist ceremony” led by the Buddhist monk Kobin Chino Otogawa at theAhwahnee Hotel in Yosemite National Park.

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