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bra sister sizes

Finding bras that fit well can be challenging at times — there are so many factors that come into play, from your cup volume to your band size to projection and root height/width. Luckily, though, there are some ways to simplify the process of finding a flawless fit. Enter “sister sizes” — calculating yours is as simple as either going up one cup size and down one band size, or vice versa. And knowing your bra sister size can come in handy in a variety of ways.

Here are some of the ways sister sizing can make bra shopping easier:

Bra sister sizing can solve fit issues.

Sometimes you find a bra you love, but it doesn’t fit quite perfectly in your size. For example, say the band fits well but the cups are too big. By sizing down in the cups and up in the band, you’ll likely find a better fit. Conversely, if you find that the cups fit well but the band is too small, you could go up a band size and down a cup size to see if that works better for you. Note that merely going up or down in the cup or band size alone will cause even more fit problems — taking advantage of your sister size requires changing both! So in other words, if you opt to go up a cup size to address some unwanted spillage, if you don’t go down a band size, the band will certainly be too big with the higher cup size.

Keep in mind that sister sizing isn’t an exact sizing. So if you adjust the band and cup size and still find the bra isn’t fitting quite right, it may simply be the wrong style for you. This is why it’s always advisable to try bras in your sister sizes on before buying them.

Related: What Are Bra Sister Sizes?

Sister sizing can help with brands that run big or small.

Not every lingerie brand fits the same. Every brand uses its own fit models and measuring systems. And even within the same brand, you may find particular styles run smaller or larger — for example, a balconette or demi-cup bra may run small in the cups, while a full-cup bra, which as a general rule has more coverage, may run larger in the cups. Luckily, you can use your sister sizes to achieve a better fit in those cases.

Bra sister sizes can save the day when a bra is sold out in your size.

We’ve all been there: You fall in love with a super comfy T-shirt bra or a stunning plunge bra — the kind you feel like you’ve been searching for forever — only to find that the store no longer has your size. Sister sizes can be super helpful in these scenarios. They can also save the day when you have a particularly rare size or a particular brand you like doesn’t make bras in that size.

The bottom line: Bra sister sizes allow you to be a lot more flexible while bra shopping and at the same time, to achieve a more customized fit. Need a little help finding yours? Check out our simple yet comprehensive bra sister size chart. And happy bra shopping! Here’s hoping your sister sizes allow you to find that much sought-after perfect fit.

Related: Find Your Bra Sister Size With Our Simple Chart

We Highly Recommend

Whether you’re shopping for new everyday bras or lingerie for a special occasion, it’s always a good idea to seek out a second opinion. We know how hard it is to find bras that fit well and feel good, especially when you’re doing it on your own. If you’ve ever felt unsure about your bra size or you just don’t know where to go to find good bras, it’s time to let a bra fitter help.

Many specialty lingerie boutiques offer bra fittings. Their expert bra fitters will take the pain and frustration out of bra shopping and do all the work for you. Even better, their product knowledge can save you time and money. Plus, they know where all of the best bras are hiding.

If you’ve struggled with finding bras in the right size, it’s time to make a change. Visit our specialty store locator to find a store near you and schedule an appointment.

Happy bra shopping!

Featured image lingerie:
Elissa Strapless Bra P5011 | Elissa Bikini P5013 in Black
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Published by

Rebecca Strong

Rebecca is a Boston-based freelance writer who focuses on style, fitness, food, and travel. She has contributed to such publications as HuffPost, Elite Daily and U.S. News & World Report. When she's not writing, she can be found at home or in the studio working on the songs for her upcoming album. Her favorite bra is a black demi-cup style with all-over-lace — timeless and feminine.

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