Why is the bra band so important?

The band needs to fit quite tightly around the body, which is why it’s always made from an elastic material with a small amount of added elastane. The material between the cups on the other hand is firm to hold the cups in place. Since the bra’s wings (back and sides) are elastic, the band will stretch. It’ll take about two weeks for a newly bought bra to adjust to the shape of the body, so make sure that it’s not too loose the first time you try it on.

“If you can pull the band 5 cm away from your back then it’s the perfect size”

How tightly should the band fit?

We usually say that if you can pull the band 5 cm away from your back then it’s the perfect size. The band shouldn’t fit so tightly that it becomes uncomfortable or chafes. This is a balancing act for women with a heavy bust: to provide proper support, a bra band needs to fit more tightly for women with large busts compared with those with smaller busts. It’s the same reason we make bras intended for larger sizes with wider shoulder straps and sturdier materials and construction in the cups. All the parts of a bra work together to reduce the stress on any one piece.

The wider the band the better it supports the bust. Pictured is FLORAL SUN.

Does a wider band mean better support?

The wider the back and sides the better the support, that’s true for all types of bras, both with and without an underwire. The underwire actually spreads the support to the back, sides and cups. The wider the band, the greater the area over which the support is shared.

“The underwire spreads the support to the other parts of the bra”

How the underwire spreads the support to the other parts of the bra, including the wings (the sides and back)

The fastening matters
The fastening at the back of a bra is nearly always adjustable; three positions is standard. When a bra is new, you should always use the outermost position and then move the fastening inwards as the bra stretches. If you buy a bra that’s about the right tightness on the innermost position, you have no options for adjusting the fit later.

When the bra is new it should fit perfectly when fastened on the outermost position.

Certain models use a front closure, which makes them easy to take on and off for women who have difficulty with rotational movements or have pain in the body. The downside is that you can’t use an adjustable fastener on front-closing models because it would change the spacing between the cups.

An example of a straight-cut back without a fastener. Pictured is COTTON LACE with front closure. This model has a wide and sturdy back.

Number of hook and eye fastenings

You usually start with two or three vertical hook and eye fastenings on smaller cup sizes which then gradually increase in number; this varies from model to model. Certain models with extra wide bands start with four fastenings on the smallest size.

*STAY FRESH has four vertical hook and eye fastenings even on the smallest size. The shoulder straps on this bra go all the way to the hook and eye: a so-called leotard cut.*

Back shape
On bras with wide sides and full cups, you usually have a U-shaped back between the shoulder straps to make it look neater whilst still providing the same amount of support. A U-shaped back is the most common cut on the market today, but there are also bras that have a straight or wrestler back: a so-called T-cut.

COTTON DOTS bra without underwire has a classic U-shaped back

“The band provides more support than the cups and shoulder straps combined!”

AMSTERDAM underwired bra has a straight-cut back with three hook and eye fastenings in the smallest size.

The bra band should sit in a straight line

If you stand in profile in front of the mirror and look at how your bra fits, the lower edge should be at the same height all the way around, in other words the back shouldn’t be pulled upwards. If that’s the case then it’s likely that the band size is too big and you’ve adjusted the shoulder straps too tightly.

“The bra should sit in a straight line if you look at yourself in profile”

For an optimal fit and shape, the bra should sit straight at the back and not be pulled upwards.

There are cases when it can be difficult to avoid the band being pulled upwards, and that is on models with shoulder straps that are narrowly positioned on the back. When you make these shoulder straps shorter there’s a tendency for them to pull the middle of the back upwards since they’re so close together. However, the general rule of thumb is that if the back of the bra is being pulled upwards you need to tighten the fastening by one position.

FLAMES underwired bra with a U-shaped leotard back and extra narrow shoulder strap placement to stop slipping

JOY is a neater bra with a regular distance between the shoulder straps, U-shaped back and sturdy mesh material.

How to use a bra extender

If the band is bunched up around the body but the bra fits well otherwise, you can use a bra extender that attaches to the fastener. It’s perfect if you’ve gone up in weight but like a particular bra and want to be able to keep on wearing it. Or perhaps you’ve just bought a new bra and know that it will fit well once it’s adjusted to your body. Bear in mind that if you use a bra extender the shoulder straps will end up further apart. If you usually have problems with shoulder straps slipping down despite them being tightened then a bra extender is not an ideal solution.

Circumferences can vary within the same size

You might have noticed that the total length of a bra, i.e. when it’s fastened and laid out straight on a flat surface, varies between different models despite them being the same size! This is partly due to the materials; different materials stretch different amounts when they’re on the body. Certain materials are more elastic than others. In our detailed materials guide, we describe the advantages and disadvantages of different textile fibres used for underwear.

“Whether or not a bra has an underwire affects its circumference”

Another factor that plays in is whether or not the bra has an underwire. On an underwired bra the front can’t stretch as much because the underwire is stiff, that’s why we make the wings longer than on non-wired bras in the same size. Read more about that here.

"It’s how the bra fits on the body that determines it’s size, not when it’s not being worn."

How do you find the right bra size?

The most common mistake women make when they’re trying to find their bra size is measuring too loosely around the body. This results in a band size that is too big and cups that are too small. If you’re unsure which size is right for you, you can measure using our size chart or contact our customer service by email, phone or on social media and they’ll be happy to help you. They’re experts at finding the right sizes for women without meeting them in person. Read more here about how our customer advice team work in our interview with Ida, the head of customer service for Miss Mary.