It's Official: These Are the 15 Most Popular COS Buys of Summer 2026
COS's expensive-looking buys are the best on the high street. These 15 summer buys are already cult favourites.
It will come as no surprise that COS features heavily in my wardrobe. Since its arrival on the British high street, the brand has carved out an aesthetic of clean lines, exquisite tailoring and high-quality staples that are often case and point for finding expensive-looking pieces on the high street. Whether you're searching for the perfect white T-shirt or adding a selection of elegant dresses to your collection, the brand executes refined minimalism with ease every single season. In turn, a series of It styles have already become cult buys for in-the-know fashion people this summer.
Florrie wears the COS Ribbed Tank Top (£15) and Cotton Straight-Leg Drawstring Trousers (£65)
Whilst summer has only just officially begun, COS has been offering up the best of its warm-weather collection since the first ray of sunshine, and a series of sleek best-sellers have come to the fore. By striking the perfect balance of high-quality fabrics, intricate details, and considered silhouettes, COS makes its affordable pieces look like investment buys. This season, light cotton and breezy linen are applied to relaxed trousers and tailored shorts for an instantly polished effect. Dresses are formed in languid silhouettes and pared-back designs, ready to be accented with sleek accessories, like the new raffia basket bag that is on everyone's wish list.
Alongside, there are the classics. The perfectly cut T-shirt, the simple yet hard-working tank top and the loose linen shirts—staple summer buys that are worth spending a little more on as they'll earn their keep in your wardrobe for years to come. Now, I've rounded up the best-selling COS buys for summer 2026 to shop before they inevitably sell out.
Shop the COS Summer 2026 Best-Sellers
1. Tiered Gathered Midi Dress
This dress is so classic, you'll reach for it every summer.
2. Cotton Straight-Leg Trousers Drawstring Trousers
Comfortable, sleek and warm-weather ready.
3. Ribbed Cotton Tank Top
A simple tank top features in so many of my staple summer looks.
4. Pleated Belted Linen Shorts
COS does tailoring oh-so well.
5. Gathered-Neck Jersey Tank Top
The soft ruching instantly elevates this top beyond the high street.
6. Riviera Hand-Woven Tote Bag
Currently in my basket.
7. Gathered Jersey Dress
If you told me this was triple the price, I'd believe you.
8. Wide-Leg Denim Shorts
Long length shorts are a sophisticated summer staple.
9. Oversized Short-Sleeved Linen Shirt
My linen is working overtime in this 30-degree heat.
10. Minimal Leather Sandals
Act fast! These refined sandals are already selling out.
11. Ruched-Waist Midi Skirt
This skirt will easily outlast the moving trends.
12. Clean Cut T-shirt
If you buy one white Tee this summer, make it this one.
13. Tailored Linen Mini Dress
For those who prefer a mini.
14. Open-Back Halterneck Top
I'm pairing this top with jeans, linen, shorts and more.
15. Facade Straight-Leg Jeans
COS is known for its excellent denim selection. Opt for light washes in the summer months.
16. Mini Cavatelli Clutch Bag
The Cavatelli clutch is highly sought after.
Shop More Best-Selling High Street Buys
The viral jacket is back, now in a breathable linen version. Don't wait around, this is sure to sell out fast!
These bold trousers have already sold out once. Now, there's a restock.
I turn back to fresh white dresses every single year.
This bag comes in so many sleek shades.
All the finer details make this top look triple the price.
Another COS buy that deserves calling out.
The black version has already sold out, but personally I prefer the white.
Save for work, date night, and weekend looks.
Nothing says summer quite like sunny yellow.
I've tried these on and can confirm they're equally chic and comfortable.
