Bras are surprisingly complicated for something Ariel whipped together with two clamshells and some string. There are quite a few things that might be wrong with your bra but it’s not immediately clear how you should change the size. Here’s a guide that’ll help you find the right fit and get rid of bras that aren’t good enough.

Band is Riding Up

If your band is riding up and creating an arch on your back, it means the band is too big. This is crucial to a comfortable bra, since the band provides the majority of your support. Try going down a band size while sticking to the same cup size.

Band is Uncomfortably Tight

This usually means that your band is too small. Try your bra on backwards (with the cups on your back and the band just under your boobs). If it fits fine, it means your cup size was too small and you need to go up. If it’s still uncomfortable, try going up a band size.

Quite a lot of women prefer a looser band than they technically should do. Since there are usually 2-4 rows of hooks, if you’re in-between band sizes it’s usually more comfortable to go up a band size and use the smallest row, than to go down and have your bra feel too tight throughout the day. Just make sure your shoulders are comfortable and the back of your bra isn’t riding up.

Straps Are Digging into My Shoulders

Red, sore shoulders at the end of the day mean that your band is too big; your band is meant to provide the majority of your support. If it fails, your shoulders take up the slack. Go down a back size and see whether that’s better for you.

Straps Keep Falling Down

The first thing to try is adjusting your straps. If that doesn’t work, it could mean that your band size is too big and the straps are too wide-set for your frame. Try a smaller back size to see whether it solves the problem.

Cups Have Wrinkles

Cups with wrinkles or gaps are a tell-tale sign that your cup size is too big for you – you shouldn’t see a gap between your boobs and bra, and it should feel fairly snug without cutting in or causing the dreaded 4-boob. Try going down a cup size or changing the bra type – sometimes a plunge will fit just right but a balconette will gape, depending on your shape. (I didn’t mean to rhyme).

Cups are Overflowing

Overflowing cups, whether it’s over the cup or in your armpit, show that your cup size is too small. It could also mean that the bra is the wrong shape for you and you should try another style. I can’t wear plunge bras throughout the day since my boobs make a bid for freedom through the middle, but balconettes in the same size are fine. Finding the right bra style for your shape is just as important as finding the right size.

There’s a Gap Between the Underwires and My Breasts

Underwires should sit just where your breast tissue starts, but different shapes make it difficult to find the right fit. If your underwire is firmly on your ribcage, with quite a bit of space between it and your breast tissue it probably means that your cup size is too big. Or you need to try another bra style with a narrower fit.

Underwires are on My Breast Tissue

The other side to this is that the underwire is actually on your breast tissue which can be really uncomfortable. Try going up a cup size or trying another style of bra with a wider fit.

The Centre of the Bra Doesn’t Touch My Chest

If the centre of your bra (the gore) isn’t sitting on your sternum, it usually means your cups are too small. If that’s the case, you’ll have cleavage in the way of your bra and need to make more room for your boobs with bigger cups. The other possibility is that you’re a bit too ‘close set’ for your bra and need to look at other styles. Balconette bras, for example, don’t work too well for a lot of ladies with close-set boobs since they force them apart with quite a wide gore.