The Complete Bra Fitting Guide

Why Bra Fitting Matters

A poorly fitted bra doesn't just feel uncomfortable — it can cause long-term back and shoulder pain, skin problems, and posture issues. For larger busts, a well-fitted bra makes an enormous practical difference to daily comfort. For smaller busts, the right fit provides the support and shape the wearer is looking for.

How to Measure Yourself

Band size: Measure around your ribcage directly under your bust. Breathe out normally and take the measurement snugly. Round to the nearest even number — this is your band size.

Bust measurement: Measure around the fullest part of your bust, keeping the tape parallel to the floor. Don't pull tight — let the tape rest against the skin.

Cup size: The difference between your bust measurement and your band measurement determines your cup size. Each inch of difference is roughly one cup size: 1 inch = A, 2 inches = B, 3 inches = C, 4 inches = D, 5 inches = DD/E, and so on.

What a Well-Fitted Bra Feels Like

• The band sits level around your body and doesn't ride up at the back
• You should be able to fit two fingers under the band — but not more
• The underwire (if present) sits flat against your ribcage and the wire does not rest on breast tissue
• Cups fully contain the breast tissue without spillage or gaping
• Straps stay on your shoulders without digging in — they should carry only about 10% of the support
• The centre gore (between the cups) lies flat against your sternum

Common Fitting Mistakes

Too large a band with too small a cup: The most common fitting error. Going up a band size and down a cup size — or vice versa — while maintaining the same cup volume is called "sister sizing". For full busts, the correct band is usually smaller and the cup larger than most people wear.

Straps doing all the work: If your straps are dug into your shoulders, your band is too big. Tighten the band first; straps are for adjustment, not primary support.

Finding Bras for Full Busts

Full-bust bras (D+ cups) from specialist brands offer far better support and fit than generic high-street brands. Look for brands that specifically design for larger cup sizes — construction, engineering, and fabric quality are meaningfully better.