It’s True: COS’s Best-Selling Arch Jeans Are Now 20% Off

Alongside identifying the next It item, a key part of my role as shopping editor is to dig into the data to discover the items that our readers actually adore. Last year, one particular pair of jeans outpaced the rest, and from the first spike in sales, the justified popularity hasn’t ceased. Now, as part of Black Friday, the beloved COS Arch jeans are 20% off in the COS Black Friday Sale.

As soon as I saw the interest in these jeans beginning to grow, I headed out to see if they lived up to the hype. In short, they did. COS has long been a brand that fashion people and our own editors turn to for excellent denim, alongside the series of standout cashmere and accessories it offers. The cut of these jeans is what propels them into the best-seller category. True to form, COS brings a contemporary edge to a classic with a subtle barrel-leg silhouette that feels fresh without straying from our elegant wardrobes.

Bridging the gap between straight-leg cuts and bold horseshoe shapes, the Arch jeans are the perfect midpoint. The cut is spot on, the sizing is true, and the relaxed nature of the jeans ensures that they’ll be a pair you dress up and down with ease. Alongside my treasured straight-leg jeans (which are also on sale this Black Friday) and playful wide-leg silhouettes, when I want something a little different, it’s the COS Arch jeans that I turn to.

As I’ve worked on the Black Friday sales for years now, I know just how fast the COS Black Friday deals move. So, scroll on to shop the Arch jeans before they inevitably sell out, and shop more excellent denim deals below!

Black Friday will fall on Friday 28 November 2025, and you can expect deals across the whole weekend and into Cyber Monday, which falls on Monday 1 December 2025. Our editors will be busy compiling the best of the Black Friday savings, whether it be clothing deals or beauty tools deals for you.