Here on the Cosmo Fashion Desk, we love keeping up with all the latest trends and finding ways to incorporate new-season looks into our existing wardrobes. But there’s something to be said for the staying power of simple staples – a plain white t-shirt, a pair of tailored black trousers. These items often form the basis of every ensemble, but there’s nothing to say they can’t receive a little trend treatment, too.

This season, we’ve noticed square necklines appearing across a number of styles, but this subtle design detail has a big impact when applied to a basic like a tank top. Instantly adding form and a contemporary feel, square necklines are also considered to universally suit almost every silhouette.

The wide, angular shape visually balances the width of the hips, working to create an hourglass silhouette, while also providing a lengthening effect to the neck and torso thanks to the vertical sides of the square shape. And, depending on where the horizontal edge of the neckline sits, it can provide elegant coverage for bigger busts alongside offering a complementary look for those with smaller busts, thanks to the structured design.

street style paris fashion week menswear spring/summer 2026 day four
Claudio Lavenia//Getty Images
A guest outside the Dior SS26 show during Paris Fashion Week
street style at copenhagen fashion week ss26 day 4
Christian Vierig//Getty Images
A guest during SS26 Copenhagen Fashion Week

Square-neck tank tops can still be worn as usual, considered as layering pieces and a base to an ensemble. But, they’re trend-led enough to work as a standalone item too. Pair it with a midi skirt and sandals to balance the casual vibe and polished feel, or dress it up as a ‘jeans and a nice top’ outfit when accessorised with statement jewellery and kitten heels.

When it comes to easy and affordable ways to update your wardrobe essentials, it doesn’t get better than Marks & Spencer’s Cotton Rich Square Neck Spaghetti Strap Vest. With a super flattering high neckline and delicately feminine thin shoulder straps, it comes in four wearable and trend-led colourways – black, white, olive green and red. And, at just £8 each, we’re tempted to snap one up in every hue!

m&s cotton rich square neck spaghetti strap vestpinterest
Marks & Spencer

Shop some of our favourite, most affordable square neck tank tops available to buy on the high street right now:

M&S Cotton Rich Square Neck Spaghetti Strap Vest

Cotton Rich Square Neck Spaghetti Strap Vest
Credit: Marks & Spencer

Next Lemon Yellow N. Premium Square Neck Halter Top

Lemon Yellow N. Premium Square Neck Halter Top
Credit: Next

TALA 365 Square Neck Vest

365 Square Neck Vest
Credit: TALA

Next Black Square Neck Vest

Black Square Neck Vest
Credit: Next

Follow Alex on Instagram.


Headshot of Alexandria Dale
Alexandria Dale
Digital Fashion Writer

Alexandria Dale is the Digital Fashion Writer at Cosmopolitan UK. Covering everything from the celebrity style moments worth knowing about to the latest fashion news, there’s nothing she loves more than finding a high street dupe of a must-have designer item. As well as discovering new brands, she’s passionate about sustainable fashion and establishing the trends that are actually worth investing in. Having worked in fashion journalism for six years, she has experience at both digital and print publications including Glamour and Ok!