Backless Jumpers UK: What to Wear Under One and How to Style It

A backless jumper looks like a classic knit from the front but has an open, cut-out or low back. It's often finished with a bow, ties or a lace-up detail. It's the easiest way to make knitwear feel like a party outfit: cosy and covered at the front, with a surprise at the back. The most common question is what to wear underneath. The short answer is a stick-on bra, a low-back bra or a deliberate bralette. Below we cover every option, how a backless jumper should fit and how to style one from Christmas parties to Sunday lunch.

Browse all knitwear in our sweaters and cardigans collection.

Our Backless and Open Back Jumper Picks

• Best for parties: Bow Back Backless Festive Jumper, £31.99. A fully open back finished with a bow, in black or fiery red. Made from 65% acrylic and 35% polyamide, UK 8–18 (S–XL).
• Best everyday bow back: Back Bow Knit Sweater, £39.99. A clean front with a feminine bow at the back, in a soft 50% viscose blend. Apricot, sizes S–XL.

What to Wear Under a Backless Jumper

This decides whether the look feels polished or awkward, so it's worth planning. Here are the options, from most invisible to most deliberate:

1. Stick-on (adhesive) bra

A stick-on bra is invisible from behind and gives light lift. It's best for small to medium busts and fully open backs. Apply it to clean, lotion-free skin.

2. Low-back or plunge-back bra

The band dips down to the lower back, so it suits jumpers that open at the upper or mid back. It gives more support than adhesive styles, which helps if you have a fuller bust.

3. Bra converter strap

A strap that lowers the back band of a bra you already own. It's a cheap fix for jumpers with a moderately low back.

4. A bralette you're meant to see

The fashion approach: a lace or satin bralette, or a slim cami, in black or a matching colour. A visible layer looks intentional, gives full support and is the most comfortable option for a long night.

5. Built-in support or nipple covers

For small busts and casual wear, silicone covers under a thicker knit are often enough.

Tip: try your outfit on and check it in a mirror from behind, in movement. Reach forward, sit down and raise your arms. Backless knits open more when you move.

How a Backless Jumper Should Fit

• The shoulders should sit in place. If the jumper slides off when you move, it's too big and the back will gape.
• The open back should lie close to the skin, not flap away from it. Bow and tie backs let you adjust this.
• Length matters. A cropped or waist-length jumper suits high-waisted trousers and skirts. A longer jumper works with leggings and slim jeans.
• Between sizes? Go for the smaller size so the back stays neat. Check the size chart on each product page.

How to Style a Backless Jumper: 8 Outfit Ideas

1. Christmas party: the red Bow Back Festive Jumper with faux leather trousers and heels. Try the Black Faux Leather Crossed Waist Leggings (£24.99).
2. Date night: black backless jumper, satin midi skirt, pointed boots and gold earrings. Keep your hair up to show off the back.
3. Office party: a backless jumper under an open blazer. It's covered at your desk, then take the blazer off for the evening.
4. Weekend: the Back Bow Knit Sweater with straight jeans and trainers. Pretty, but relaxed.
5. Flares and platforms: high-waisted flare jeans (£55.43) lengthen the leg under a cropped knit.
6. Festive drinks: a backless knit tucked into a velvet or sequin skirt. See our sequin styling guide for more party sparkle.
7. Sunday lunch: wear it back to front (if the cut allows) for a covered back and a twist at the neckline. Check the fit first.
8. Outdoors: a long wool coat over the top. The open back is a reveal when you take the coat off indoors.

Hair, Jewellery and Finishing Touches

• Hair up: a sleek bun, a claw clip or a low ponytail. Long loose hair hides the detail.
• Back necklace: a long chain worn backwards, or a lariat, draws attention to the open back.
• Skin prep: a little body lotion on the shoulders and back makes the look feel finished. Apply it after a stick-on bra, never before.

How to Care for Backless Knitwear

• Wash cold on a gentle or wool cycle, or by hand, and turn the jumper inside out.
• Untie bows and ties before washing so they don't knot or stretch.
• Dry flat to keep the shape. Hanging stretches the open back.
• Fold it to store, don't hang it.

Quick Questions

Shop Backless Jumpers at Fashionfitz

Make your knitwear party-ready with the Bow Back Backless Jumper, or browse more in our sweaters and cardigans. For more festive knit ideas, read our Christmas jumper trends guide.