I became a bob girl in a moment of wild optimism and mild delusion – though, in fairness, I was a hormonal teen who hadn't had a bob since my Lord Farquaad cut circa six years old, so this was less a reinvention and more a full-circle crisis. But I digress...

Sitting under the salon cape like I was about to be knighted, I declared my confidence in the chic chin-length cut and ten minutes later, I watched a small mammal's worth of my hair slide to the floor. That's when I realised: I had gone too chic. In other words, the length was now so short that its ends and my shoulders had different postcodes. *War flashbacks*

Here's the thing no one tells you ahead of the big bob chop: the biggest mistake is going too short, too soon. Sure, we're all for living in the moment, but when it comes to the permanency of a haircut and the lengthy process of growing it back, we need to treat a transformative bob cut as a considered commitment, not a spur-of-the-moment decision.

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Valentina Frugiuele//Getty Images

But don't just take my word for it. As Keeks Reid, Beauty Director at Cosmopolitan UK and trained hairstylist, explains, "The biggest mistake people can make when cutting a bob after having super long hair is going too short initially." With over 10 years of experience in the industry, she's seen it happen time and time again – people leaving the salon convinced they hate their new look, when actually, "it's because it's too short and a big drastic change."

Her advice is simple. "I would always recommend going a fraction longer than you think, and then cutting more off if you want." Because there's also something she calls "styling mileage" – that extra bit of length you don't think about. As she puts it, it's "the little extra length you need for waves and curls and texture if you are cutting straight hair."

The takeaway? Start longer! Think of a lob (long bob) as your training wheels. Now, that's not to say you can't eventually go for a chin-length bob, dabble in a fringe or experiment with texture – but with ease.

Everyone's clicking on...

Remember: you can always take more off; you can't glue it back on.

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Headshot of Lia Mappoura
Lia Mappoura
Beauty Writer

Lia Mappoura (she/her) is the Beauty Writer at Cosmopolitan UK, with over four years of experience reporting across the brand's print, social, video and digital platforms. Lia covers everything from emerging trend analysis to viral celebrity hair and makeup moments, making her an expert at spotting the season’s next big beauty look (before it takes over social media feeds).

In 2025, she was named The Rising Media Star at the Love Perfume Awards with The Perfume Shop, recognised for her outstanding digital fragrance content and for building genuine authority within the space. She is passionate about challenging outdated beauty stereotypes, championing inclusive representation in beauty, and educating readers on the trends, products and conversations shaping the industry today. Follow her on Instagram or find her on LinkedIn