In Defence of Underwires: The Key to Support for D+ Cups

Underwires: a relic of a time when women's undergarments didn't consider their comfort, or a steadfast necessity? Is this a classic case of design and engineering not prioritising women's issues, or is there a reason they've stood the test of time?

The reason we still use underwires, is because they're really good at their job, especially in the best fuller bust bras. The purpose of underwires is to provide the foundation of shape for the rest of your bra - they're what produces a nice rounded shape, even with zero padding or foam in the cups. You can think of them sort of like the poles in a tent, they provide the shape and structure of your cups.

Another key job underwires do is hold your tissue where you want it, especially under your arm. In a well-fitting bra, all of your side breast tissue will be pulled forward and encapsulated inside the cup, with the wire acting as the barrier between boob and non-boob. Without a wire, your tissue is free to float out under your arm, and you won't get the same forward projection, shape, or definition.

Underwires are made of metal because they have to be strong and rigid, to hold your tissue where you want it and create mould your breasts into a specific shape. If they were soft or too flexible, they wouldn't be able to do their job.

Of course, your goal with your bra might not be strictly shape! There's nothing wrong with wire-free bras - you're often still able to get nice support and next-level comfort in a wireless bra for big boobs like our Wire-Free Crop. Without underwires, the shape you can expect will just be a bit more relaxed and natural.

However, if you've been wearing wire-free options because you consider underwires to be painful or unwearable, it might be worth getting re-fitted. The majority of the time, if your underwires are bugging you, the problem is the fit and not the wires themselves.

To be comfortable, underwires have to be the right size and shape to fit on your body like a puzzle piece. They should be comfortably tucked right underneath the roots of your breasts, tracing all the way underneath, and ending far enough back through your torso to capture all of your side breast tissue.

Here are the most common underwire-related fit issues we see in the fitting room: 

Underwires sitting on top of breast tissue

In our industry, there's something known as a "boob hat." A boob hat is a bra that is sitting on top of your boobs, covering them, but isn't actually providing any structural support. Boob hats won't provide the lift and shape you're probably after, and they don't do their job of distributing the weight of your bust across your whole torso and giving your back a break.

One of the tell-tale signs that your bra might be a boob hat is your wires sitting on top of breast tissue. This almost always happens near your arm, with your wires sitting on top of side breast tissue.

A quick trick to tell if your underwire is sitting where it should be under your arm, is to press in near the top of your underwire, into your side. If your boob moves forward when you do that, your wire isn't coming back far enough and is actually sitting on your breast. If it just feels like you're pressing the wire into your rib, and your breast doesn't move, you're good!

Underwires moving around throughout the day

If your wires are comfortable when you first put your bra on in the morning, but move around throughout the day and cause irritation or poking, you're not alone. 

There are a few reasons this might be happing, but the most common one is that your band is too big. Underwires are only truly comfortable with a firm band - I know it sounds counterintuitive, wouldn't a looser band be more comfortable?

The reality is that your band needs to be firm enough to hold your underwires in place all day, firmly tacked to your chest. Again, underwires are like puzzle pieces on your body, they have one spot they want to sit. If your band isn't firm enough to keep them there and they can shift around to places they aren't supposed to be, that's when you get irritation or even potentially injury.

Breast tissue escaping out from underneath underwires

If your boobs can leak out the bottoms of your cups, resulting in your wires sitting on top of your breasts, it's definitely time for a new bra!

The cause of this might be a little different for everyone, but it's most often a result of a cup size too small and a band size too big. Your bra's cups might not have enough volume to contain all of your tissue, and your band might not be firm enough to hold your wires firmly against your body. 

Wire digging into your sternum

This one is where underwire shape comes into play - even if you're wearing the correct size bra, wires poking you anywhere is a sign that the shape of this underwire might not be for you.

Underwires are all U-shaped, but the specific angle and length of the U changes from brand to brand, and style to style. You might be better suited to a wider underwire, a more narrow one, or a longer or shorter wire.

If your wires only poke you on your sternum, it could be worth trying a style with a lower centre plunge. Sometimes just getting those wires ending lower can remove the issue.

If you're sick of battling with underwires, it's time to get fitted! The best way is always in person - have a look around your area to see if there's a lingerie boutique offering fitting services for fuller busts. If that isn't an option for you (it's far too rare, unfortunately!), instead of resorting to big chain stores, reach out to us.

Fill out a complementary E-Fitting here and tell us about your wire issues, and one of our fitters will get back to you with personalised recommendations.

Let's find wires that work for you!