Maybe brunettes, not blondes, have more fun—just ask Kourtney Kardashian.

The Kardashians star recently kissed her platinum locks goodbye and officially went back to her roots. Taking to Instagram on May 21, Kourtney unveiled a jet-black look, cheekily captioning her post, "brunette4lyfe."

The Poosh founder shared a carousel of photos that showcased her new look. In one image, she slicked down her long bob, tucking the sides behind her ears and parting it in the middle. She paired her edgy 'do with a bold, black smoky eye and white overalls layered over a black-and-white Blink-182 band tee (a sweet nod to husband Travis Barker, 47). Another snapshot featured Kourtney—with a deep side part—wearing a lingerie slip dress that consisted of a ladybug print and lace trim.

The 44-year-old's transformation comes just two months after she bleached her hair blonde. In March, while enjoying a Las Vegas trip with Travis, Kourtney debuted her lighter tresses during date night at the UFC 285 event.

Kourtney, who has been blonde before, previously explained why she doesn't keep the hair color for a long time.

"I kept this hair color for only a month before dying my hair light brown with highlights," she shared on her now-defunct app in 2019. "When I was getting my highlights touched up, all of them fried off and I had spikes of hair that stuck up so I dyed my hair black and cut it short."

And while people typically go lighter in the summertime, Kourtney isn't the only star to bend the rules. Keep scrolling to see all of the latest celebrity hair transformations.

The "Say So" singer showed off her dramatic hair transformation on Instagram, debuting bright purple hair and a spooky spider design on the back of her head.

The Kick-Ass actress debuted a fresh bob haircut, which she hasn't rocked in quite some time.

The American Idol judge revived her signature style of 2008 and revealed baby bangs in a June 20 Instagram.

The Vampire Diaries actress debuted fringe bangs for the Los Angeles premiere of her new film Out-Laws in June.

The "Vogue" singer debuted an edgy shag haircut on June 11.

The Dance Moms alum proved you can be blonde and brunette at the same time with her recent hair change.

The High School Musical alum has entered her French girl era, after showing off her new curtain bangs.

The New Girl alum ditched her trademark brown hair and blunt bangs for a sky-high blonde 'do for her upcoming appearance on the '80s-based Apple TV+ series Physical.

The "Over It" artist headed into summer with a shorter cut and new hair color, debuting her blonde bob to Instagram in May 2023.

The X-Men star kissed her shoulder-length hair goodbye and debuted a pixie cut on May 26.

While attending the Louis Vuitton cruise show in Italy on May 24, Emma debuted curtain bangs—a style she often rocked in the mid-2010s.

The Sweet Home Alabama actress debuted wispy fringe bangs in a stunning selfie. 

The Poosh founder went back to her brunette roots, debuting a new look. As she put it on Instagram, she's a "brunette4lyfe."

Amid her ongoing transformation journey, the Rob & Chyna alum debuted a short pixie cut with shaved sides.

On May 15, the pop star opted for a bold hair color, rocking jet-black hair.

Helen Mirren wowed at the 2023 Cannes Film Festival, as she debuted vibrant blue hair.

Playing Lily Bloom in the film adaptation of Colleen Hoover's It Ends With Us, the actress was seen with red hair while filming scenes in New York City on May 15, 2023.

The Star Wars actress debuted her newly shaved head on May 10, writing on Instagram, "Happy without hair!"

On April 24, the Tangled actress debuted a fresh cut and fringe bangs.

The "Flowers" singer unveiled a drastic hair change, going back to her brunette roots, at The Daily Front Row's Seventh Annual Fashion Los Angeles Awards.

The TikTok star debuted a drastic hair change at Coachella 2023, unveiling a blonde bob look.

Ava Phillippe, the daughter of Reese Witherspoon and Ryan Phillippe, debuted blunt bangs in an April 4 Instagram.

The Elvis star went bald for his role as Feyd-Rautha in Dune: Part Two.

The actress debuted a long bob on April 3 that's perfect for spring.

"@craphairclub hair is giving me so much joy still," the daughter of Nicole Kidman and Tom Cruise shared on Instagram March 29 along with a photo of her 'do. "Thank you."

The Pretty Woman star showed off her fringe bangs and fresh hair color on March 27.

The supermodel debuted a pixie haircut in a March 20 Instagram, while also sharing behind-the-scenes snapshots of her photoshoot with Pop magazine.

The star debuted a red hot new 'do in March 2023.

Kourtney debuted her biggest hair transformation in March 2023.

After reverting back from blonde to brunette, the SKIMS founder zhuzhed up her signature look with curtain bangs.

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