Kendall Jenner and Hailey Baldwin Get Cheeky in Butt-Baring String Bikinis During 'Gals Weekend'

Watch: Kendall Jenner and Hailey Bieber Coordinated in Thong Bikinis on Vacation

Kendall Jenner and Hailey Baldwin had an epic girls' getaway over the weekend.

The models and BFFs jetted off to the tropics to enjoy a few days soaking up the sun by the beach (in barely-there bikinis, of course) and sipping on Jenner's brand-new 818 Tequila.

Jenner, 25, and Baldwin, 24, each shared plenty of pics on Instagram as they partied on a yacht and frolicked in the sand. "gals weekend ✔️," Baldwin captioned her post, which included a shot of her lounging on her stomach on a boat in a revealing thong bikini with a bottle of 818 Tequila by her side. Also on the boat, the model turned around to snap a photo alongside two friends who faced the water before they (most likely) jumped in to take a dip.

Hailey Bieber/Instagram

In another pic, Baldwin showed off her backside as she wore a different thong bikini while posing underneath an outdoor shower that was surrounded by palm trees. When the model wasn't showing skin in her swimsuits she got glam in vacation-ready outfits, like a black bralette and colorful patterned trouser set.

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Hailey Bieber/Instagram

It's no surprise that Jenner showed off her own skimpy style moments from the trip too. The star put her modeling skills on full display as she posed for some sultry ad campaign-like photos in a retro-patterned thong bikini and long-sleeved crop top.

She also shared a fun photo throwing her arms above her head on the beach with friends Hannah Logan and Lauren Perez by her side. "girls getaway @hannahlogann @laurenperez @haileybieber," Jenner captioned the Instagram Story photo which appeared to be taken by Baldwin.

Jenner posted more moments from their vacation including one of her signature mirror bikini selfies and a shot taken from the side as she walked past the pool.

Kendall Jenner/Instagram

Kendall Jenner/Instagram

Kendall Jenner/Instagram

Jenner and Baldwin's friendship dates back nearly a decade, and the pair recently opened up about their tight-knit relationship in the debut video for Baldwin's YouTube channel.

"We met through Kylie [Jenner]…at The Hunger Games premiere [in 2012]." You were friends with Kylie and then you realized that I was more fun," Jenner said with a laugh.

"Not necessarily! I love you both, but you and I became much closer because you started modeling and coming to New York all the time and I lived in New York," Baldwin said, "And you needed a friend…and boy did we take that city by storm."

The pair said that their relationship is surprisingly normal considering their celebrity status. "The reality is we just sit at home and drink wine or watch movies," Baldwin said before Jenner explained that they balance each other out with a "yin and yang" dynamic.

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