By Jenisha Jonchhe Researched and tested where possible Updated
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What to search for on Amazon UK
Add your UK size to the search on Amazon (for example “34G”). Not sure of it? Use our bra size calculator first.
- 1
Low-back bra with a U-shaped band
The band dips down at the back and fastens around your waist, so it hides under backs cut to the mid or lower back while the cups stay supportive.
- 2
Low-back converter strap
A short strap that hooks onto your own bra and pulls the band lower. It is the cheapest fix for a dress with a moderately low back.
- 3
Adhesive stick-on bra
No band and no straps at all, so it works with fully open backs and plunging fronts. Best for smaller to mid cup sizes.
- 4
Sew-in or pin-in bra cups
Cups attached inside the dress give shape with nothing to show. Ideal for a dress you will wear more than once.
As an Amazon Associate, My Bra Size earns from qualifying purchases. Links open Amazon UK; prices and stock are set by Amazon and its sellers. Search results change often, so a product appearing there has not necessarily been tested. Product photos, where shown, come from Amazon. How we handle affiliate links
The best bra for a backless dress depends on how low the back is cut and how much support you need. A low-back bra suits most dresses; a stick-on bra suits fully open backs; built-in cups suit fitted dresses you wear often.
Start with the dress: how low is the back?
Put the dress on and look in a mirror with your back to it. Note where the opening ends:
- Upper back (above your usual band line). A racerback or halterneck bra, or a multiway bra worn halterneck, will be hidden.
- Mid back (around your usual band line). You need a band that sits lower: a low-back bra or a converter strap.
- Lower back or waist. Choose a low-back bra with a deep U-shaped band, a longline strapless bra, or a stick-on bra.
The five options, compared
- Low-back bras. The band dips into a U at the back and wraps around your waist. They keep wires and full cups, so they work for D cups and above.
- Converter straps. A strap that hooks onto your usual bra and pulls the band down. Quick and cheap, but less stable.
- Stick-on bras. Adhesive cups with no band. They suit smaller cup sizes and deep plunges. Our guide to stick-on bras covers who they work for.
- Built-in cups. Sew or pin moulded cups inside the dress. Nothing can slip into view.
- Longline strapless bras. If the back opens only below your ribs, a longline strapless gives the most support of any option.
Which size should you buy?
Buy low-back and strapless styles in your usual UK size. If you are unsure of it, use our bra size calculator first. Stick-on bras are usually sold by cup letter only; check the maker’s chart for the cup range each size covers.
How to test it before the day
Wear the bra with the dress at home for an hour. Sit, raise your arms and dance a little. Check the back in a mirror from both sides, and check that the front neckline does not show the cup edge. If you are using adhesive, test a small patch on your skin a day or two before.
Questions people ask
What bra do you wear with a backless dress if you have a big bust?
Can you wear a strapless bra with a backless dress?
Do low-back converter straps work?
Written by
Jenisha Jonchhe
Jenisha Jonchhe is a New York-based fashion writer and designer with academic training in fashion design. She writes research-led bra sizing and fit guides for UK shoppers.
Researched from brand and retailer size guides, and tested hands-on where possible. Search results on Amazon change often, so a product appearing there has not necessarily been tested. How we research and test
