If you’ve ever been to a store to buy your bras and been frustrated by the fact that they didn’t carry your size, or if you’ve ever felt like your bra doesn’t fit right, you’re not alone. Bra sizes vary from brand to brand, but what most people don’t realise is that the sizing between brands can also vary quite widely even when they are considered the same cup size! Having an understanding of these sister sizes will help you find bras that fit better than those in your typical size.

What is a bra sister size?

bra sizes

Bras are designed in cup sizes, but people don’t come in one standard size with this system. A bra sister size chart is used to determine the correct bra size if you are wearing a different brand or if you prefer a different style from your usual one. The term sister sizes refers to the practice of finding your sister size in another brand to ensure that you have found the right size for you. This can be done by comparing your bust measurement to the bust measurements of other women with the same cup size who wear a different brand or style.

You'll have to round up if it's an even number or round down if it's an odd number. You should also consider wearing a smaller band size since sister sizes offer more room in the band area. In order to figure out your sister size, take your underbust measurement (in inches) and add five inches to get your new cup size.

Sister sizes are larger than your standard bra size and smaller than your sister’s standard bra size by one band and one cup size. For example, if your bra band size is 34, but you want to try the 36 band, you would try a sister size 34D. It can be tricky to determine which sister size to order in different brands and different styles because the construction of bras differs by brand and style. In order to find the right sister size, it’s essential to understand how bra sizing works.

Find your bra sister size

There are many different factors that come into play when trying to determine your bra size. Your band size, cup size, and your breast type all factor into the equation of finding the right bra for you. For example, if you have a larger chest with more volume or a fuller bust, then you may need to go up in band size. If you are petite framed with a smaller bust then you may need to go down in band size. Sometimes there can be variations between two bras of the same size by a different brand. So it is important to know about your unique frame, body shape and breast tissue density before choosing a new bra so that you don’t end up buying something too small or too big.

The sister size chart below will help you figure out what your equivalent bra sister size is:

Bra sister size chart

Bra Size Sister Size Up Sister Size Down
30A 32AA 28B
30B 32A 28C
30C 32B 28D
30D 32C 28DD
32A 34AA 30B
32B 34A 30C
32C 34B 30D
32D 34C 30DD
32DD 34D 30DDD
34A 36AA 32B
34B 36A 32C
34C 36B 32D
34D 36C 32DD
34DD 36D 32DDD
36A 38AA 34B
36B 38A 34C
36C 38B 34D
36D 38C 34DD
36DD 38D 34DDD
38A 40AA 36B
38B 40A 36C
38C 40B 36D
38D 40C 36DD
40A 42AA 38B
40B 42A 38C
40C 42B 38D
40D 42C 38DD
40DD 42D 38DDD
42A 44AA 40B
42B 44A 40C
42C 44B 40D
42D 44C 40DD
42DD 44D 40DDD
44A 46AA 42B
44B 46A 42C
44C 46B 42D
44D 46C 42DD

Determining bra size

Bra sizing has become increasingly difficult over time because of the rapid change in styles and designs. The good news is that most manufactures produce their clothing based on an international standard sizing system called Universal Standard (US) which makes it easier to find clothes from different brands that will fit well together on your body.

Determining bra size is as simple as measuring your underbust measurement, determining your bust measurement (usually around nipple level), and subtracting the first number from the second number. A bra that fits these measurements well should be considered a perfect fit!

How to figure out your sister size

bra sister size measuring

Finding the right bra size is a challenge for many women. Bra sizes can vary depending on the brand, style, and clothing size. If you wear a bra that is too big or too small for your body, it will not provide the necessary support and can lead to other problems like back pain. Women come in all shapes and sizes, which means there are a lot of different bra sizes available. Bra sizing can be confusing and can cause frustration when you're trying to find your perfect fit. Luckily, there's a way to simplify bra sizing by choosing your sister size. Your sister size will be the same measurement as your underbust, but with one difference: cups.

There are a few ways to figure out what your sister size is:

  • One way is to measure the band size and cup size you wear, and then compare it to the chart.
  • Another way is to find the difference between your current bra size and your desired bra size, and then subtract that number from your current bra size.
  • A third way would be to have someone measure around your ribcage under your breast, in inches or centimeters, and then find that measurement on the chart.
  • A final way is to determine the difference between your bust size and waist size, as this will give you an idea of which sister size should fit best. In order for a woman to get the most comfortable fit when purchasing bras, she must first understand her own measurements as well as know how different brands come in different sizes with their own sizing scale.

Sizes can also vary between different bra types.

The best bras for different bra types

There are many different types of bras with a variety of features, all designed to serve different purposes. Here are our favourites in the market right now.

Sports Bra

The most basic type of bra is the sports bra, which provides support and coverage while exercising. It's perfect for all body types and sizes. You need to have at least one sports bra in your underwear drawer!

T-Shirt Bra

T-shirt bras are perfect for wearing under t-shirts or other close-fitting tops; they provide a smooth silhouette without any bulky seams. This one in particular has convertible straps making it perfect for different outfits!

Demi Cup Bra

Demi cup bras offer light coverage and provide a nice shape without any nipple show through. This non-padded lacy bra will definitely give you a confidence boost!

Plunge Bra

Plunge bras give extra cleavage by pushing your breasts together in front. These types of bras are perfect for low cut tops as they won't ruin your outfit. This is a must have!

Push-Up Bra

Push up bras help lift your breasts and make them appear fuller. If you want to have support and up-lifted look, then you should definitely get this push up bra!

Strapless Bra

Strapless Bras are great for wear with strapless dresses because they keep everything in place! Your bra straps don't have to ruin your outfit anymore. This strapless bra won't slip down and will keep your girls supported all throughout the day.

All things considered...

We hope that you learned more about bra sister types. We all have had issues while trying to find the right fit. It for sure can get frustrating, but it gets better with time. Happy bra shopping, and we will see you in our next blog post!