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% offin 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!

Shop the COS Arch Jeans With 20% Off

There's something about deep indigo that always looks so elevated.

Pair with slouchy knits or take to evening with an elevated top.

Black jeans are just so versatile.

Shop More Black Friday Jeans Deals

Abercrombie & Fitch

High Rise 90s Relaxed Jean in No Fade Black

Get an extra 15% off the 30% off Black Friday sale with code AFWHOWHATWEAR.

Reformation

Cynthia High Rise Straight Jeans

They also come in petite and tall lengths!

Levi's

Ribcage Wide Leg Jeans

Levi's is known for its excellent denim.

MANGO

Low-Rise Wide-Leg Jeans

I'm always so impressed by Mango's denim offerings.

Levi

501® Levi's® Original Jeans

I constantly hear fashion people raving about their treasured 501s.

Khaite

Corben High-Rise Tapered Jeans

I've dreamt of owning a pair of Khaite jeans.

Mother Denim

The Tomcat Roller Fray - Dancing in the Moonlight

Made from a stretch denim for added comfort.

Paige

Leenah Wide Leg Jeans

Find the 30% off Black Friday deal applied at checkout.

Hush

Nessa Wide Leg Jeans

The perfect amount of slouch.

What is Black Friday?

Black Friday weekend is an annual sale shopping event that originated in the US. It marks the end of Thanksgiving and the start of the festive shopping season, resulting in the majority of well-known—and even, in recent years, smaller—brands and retailers heading into a period sale for a full four days.

When Is Black Friday 2025?

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.

When does Black Friday 2025 end?

Black Friday sales tend to run over the weekend and end on Cyber Monday, which will fall on Monday 1 December 2025.

What is Cyber Monday?

Cyber Monday is the final day of sales of the Black Friday sales period. In 2025 it will be Monday 1 December, and is typically the last chance to snap up savings.