these simple clues will help you spot when a bra doesn't fit you properly:
the band rides up at the back
If the band is riding up it is not fitting you snugly. This means it is too big or the straps are too tight – loosen the straps to see how the underband feels, remembering it's the underband that provides most of the support. When you slip the shoulder straps down the band should still hold you in place, without being so tight it causes restriction or discomfort. If you lift your arms up or move them around the band should still sit firmly in place and not move around.
shoulder straps dig in
If the straps are digging in this may be because the band is too big and not giving you enough support, meaning that the straps are doing all the work instead – try loosening the straps too see how the band feels. If, with the straps loosened the band is not supporting, try a smaller band size.
centre front is lifted
The centre front should sit flat against the body. If the centre front is pushed away from your body the cups are probably too small, so try a larger cup size.
the underwire digs in
If the underwire is digging in or pinches the breast tissue under the arm, this is a sign that the cups are too small. It's important that the breast tissue is completely held by the underwire, so try a larger cup size.
If your bust is bulging over the top of the cups, they are too small. Try wearing a t-shirt over the bra to show up any bumps. Please note, where tissue has lost elasticity you may see some bulging in half cup styles.
the cups look baggy
If the cups look baggy try a smaller size. However, if the cups fit snugly and just crease where they meet the strap, it may be that you are hollower in the chest and the bra comes too high up for your shape. In this case, try a bra with cups that finish lower down, such as a balconette.
different sized breasts
Many women have one breast slightly larger than the other, usually by about half a cup size. For some there is more of a difference. Always fit the larger breast and tighten the strap for the other. You can always use light padding too.
The front band pulls down
If the underwire sits further down your body than the crease of your breast,this is a sign that you’re wearing too small a band size. The band is sitting at a narrower place on your body.