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BRAND CLEARANCE EVENT ? Up to 60% Off - Ends Midnight Sunday

BRAND CLEARANCE EVENT ? Up to 60% Off - Ends Midnight Sunday

BRAND CLEARANCE EVENT ? Up to 70% Off - Ends Midnight Sunday

Boob & Bra FAQ

How To Find Your Bra Sister Size

Have you ever found a gorgeous bra that needs to be yours only to find it’s not available in your size? We certainly have. But fear not! Have you ever thought to try your sister size? Some of you may or may not know that you can find a bra that essentially has the same cup depth as your size and it’s known as a sister size. Win-win I hear you cry! We’re going to explain exactly how it works, so hopefully you’ll always be able to find that dream bra in a size that works for you.

As you probably already know, a bra cup size is all relative to the band size. This means a 30D is completely different to a 36D (so guys that’s why we get annoyed when you think a D cup is the most humungous size ever). As a bra band size is increasing, the relative cup volume is decreasing and vice versa. Because of this, more bra cup sizes can have the same volume, even if they do have different band sizes. What we’re trying to say is more cup sizes can actually fit your breasts!

The Rule

So how does it work? With the above in mind we’re going to pick a size to demonstrate. If you’re fitted as a 34FF but find that the back band is too tight, you can go up to a 36. As the rule states, if you go up a back band, you must go down in the cup to compensate. This would take you to a 36F. However, if you find that a 34FF is too big in the back, you can go down to a 32. This means you then have to go up in the cup, making you a 32G. Essentially the cup depths are the same. Even if you find the band and cup to fit fine, but fancy trying a sister size (if that’s all there is) then this is the easy rule you need to follow.

We also understand that different brands can vary in the way they fit, so this technique could come in handy if you’re trying a new brand and you find that your usual size isn’t working.

Still not sure what this all means? We explain Sister Sizes in more depth here!

Of course wearing the size you’re fitted as is key, but if you find your sister size and it works for you, then why not? Some of you may find your bra sister size fits better or worse, it’s all down to you and your boobs. Have you ever used the bra sister size technique to get that dream bra? Tell us in the comments below!

Grace x

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