Chrissy Teigen, Nina Agdal and Lily Aldridge strike a playful pose in the picture topping the magazine's annual swimsuit edition.
The image was to be unveiled Thursday on ABC's "Jimmy Kimmel Live!" The issue hits newsstands and digital formats next week.
Aldridge said in an interview Thursday she was "in shock" over her selection.
"It's the most incredible honour to be a Sports Illustrated cover model," she said.
Especially since it's the 28-year-old Victoria's Secret model's first time in the magazine.
Even though Teigen has appeared in the swimsuit issue five times before, she never expected to land on the cover.
"It's the ultimate surprise, and it's the best feeling in the world right now," said the 28-year-old, who recently married musician John Legend.
The last time multiple models appeared on the cover of the magazine's swimsuit issue was in 2006.
So what made the trio's photo stand out? Teigen said she thinks it's because they instantly bonded as buddies and got along swimmingly during the shoot, in the Cook Islands, off the coast of New Zealand.
"The smiles that you're seeing are genuine," she said. "We had a good time, and it shows in the picture."
The models said the most exciting thing about their Sports Illustrated cover status is what it might mean for their futures.
"Getting to be on the cover, we're all going to be household names," Aldridge said. "It's incredible what it does for your career and where it can take you."
Teigen joked that she doesn't know what else to do now and feels as though she should retire.
"Nothing is going to compare to this," she said. "This is pretty epic."
Follow AP Entertainment Writer Sandy Cohen at http://www.twitter.com/APSandy