Lingerie Size and Fit FAQ: Cups, Bands and Briefs Explained

Quick answer

A well-fitting bra band sits level and snug on the loosest hook, the centre gore lies flat against your sternum, and the cups contain your breast tissue without gaping or spilling. Briefs should lie flat at the waist and leg openings without cutting in or riding up. If you are between sizes, start with the band size and adjust the cup, then treat the brief as a separate fit decision rather than assuming it matches your bra size.

How should a bra band feel?

The band provides most of a bra's support, so it should feel firm but not painful. Fasten a new bra on the loosest hook: as the elastic relaxes over time, you can move to the tighter hooks and keep the same fit. You should be able to slide two fingers under the band at your back, and the band should stay level all the way around rather than rising up. If it rides up, the band is likely too large or the cups are too small.

Why does the band size matter more than the cup?

Cup volume is relative to band length, so changing the band changes the cup. If you go down a band size, go up a cup letter to keep roughly the same volume; if you go up a band, go down a cup. This is why a 34C and a 36B can hold a similar amount, even though the labels look different. Always test the band first, then fine-tune the cup.

What do cup gaps and spillage actually mean?

Gaping at the top of the cup usually means the cup is too large, too tall, or the wrong shape for your breast tissue. Spillage over the top or at the sides means the cup is too small or too shallow. If the wire sits on breast tissue rather than flat against your ribcage, the cup is likely too small. A cup that wrinkles at the bottom but gaps at the top often points to a shape mismatch rather than a pure size issue.

How do I choose a brief size?

Brief sizing is not tied to your bra size. Measure your hips at the fullest point and compare that to the brand's size chart, then consider the rise you prefer. A mid-rise brief should sit on or just below your hip bones, while a high-rise style reaches toward your natural waist. If you are between sizes, size up for comfort in lace or silk, which have less stretch than elasticated cotton.

What if my briefs dig in or ride up?

Digging at the leg openings usually means the brief is too small or the elastic is too tight for your shape. Riding up at the back often means the waistband is too loose or the rise is too low for your torso. Check that the gusset sits flat against your body and that the side seams are not twisting. If you need a different rise or more coverage, change the style rather than only the size.

Fit FAQ: quick checks before you buy

How do I know if the band is too tight?

You can slide two fingers under the band at your back, and it does not leave red marks or restrict your breathing. If it does, go up a band size and adjust the cup down. Test on the loosest hook so you have room to tighten later.

Should the centre gore touch my chest?

Yes, in most bra styles the centre gore should lie flat against your sternum. If it floats, the cups are often too small or too shallow. A floating gore is a cup issue, not a band issue.

Can I wear the same size in every brand?

No. Sizing varies by brand and style, especially between lace, silk, and stretch fabrics. Always check the specific size chart and read the fabric composition. Treat each new style as its own fit decision.

Sets that show how fit details differ

• Simone Lace Boudoir Bra & Ouvert Brief Set: Simone Lace Boudoir Bra & Ouvert Brief Set: soft cup lace triangle bra with adjustable back, open back brief with 24k gold-plated fastening, signature lace with silk and bespoke fishnet embroidery, designed in the UK and made in Portugal. The adjustable back on the triangle bra lets you fine-tune band tension, which is useful if you are between band sizes. The ouvert brief is a deliberate style choice, so check whether an open back suits your comfort and coverage preferences before buying.
• Fleur du Jour Blush Triangle Bra & Brief: Fleur du Jour Blush Triangle Bra & Brief: all-silk triangle bra fully lined in silk with 24 carat gold plated hardware, paired with a mid-rise brief with a front silk panel. Silk has less stretch than elasticated fabrics, so the band and brief will feel firmer and less forgiving than a stretch style. If you are between sizes, consider sizing up in the brief for a more comfortable fit.