Strapless Bra Sizing Guide: Getting the Band and Cup Right
For a strapless bra, measure your band and bust exactly as you would for any bra, then consider sizing down one band size from your usual fit. A strapless band needs to work harder without straps sharing the load, so a snugger fit is usually more secure and more comfortable over a full day.
Getting strapless bra sizing right matters more than with a strapped bra, since there's no strap adjustment to compensate for a slightly-off band fit.
Measuring Band and Bust
Measure snugly around your ribcage directly under your bust for your band size, and around the fullest part of your bust for your cup measurement. The difference between the two gives your cup size, exactly as with any bra style.
Why Strapless Bras Often Need a Snugger Band
Without straps sharing any of the load, the band alone is responsible for keeping the bra in place. A band that would feel comfortably snug on a strapped bra can feel slightly loose once the straps are removed. That's why sizing down one band size is a common, sensible adjustment. If it still doesn't hold, see how to keep a strapless bra from sliding down.
Getting the Cup Right
Cup size shouldn't change between strapless and strapped styles. If you size down the band, size up the cup correspondingly to keep the same cup volume. Gaping at the top of the cup, or spilling at the edges, both signal the cup size needs adjusting. If you're above a DD cup, our honest guide to strapless bras for a fuller bust is worth reading first.
Frequently asked questions
Should I always size down for a strapless bra?
Not always, but it's worth trying if your usual size feels at all loose without straps. Many women do find one band size down more secure.
What if the band feels tight when I size down?
A snug fit is correct, but it shouldn't dig in or leave marks. If it does, that specific size is too small. Try the size between.
Do all strapless bras fit the same across brands?
No. Always check the specific size guide for each style, as fit can vary meaningfully between brands and constructions.
Can I get remeasured if I'm unsure?
Yes, a proper measurement or fitting is always worth doing if you're between sizes or unsure, particularly for a first strapless purchase.
See our complete strapless bra buying guide or shop sizes 34-42, A-DD. Free UK delivery, 30-day returns.
