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bra sizes

Ever wonder why one lingerie brand fits you better than another? Not all bras are created equal. Each lingerie brand has its own grading and sizing system for bras.

What does this mean for you? Well, first of all, you may not wear the same bra size or find the same fit style to style in every lingerie brand. Secondly, you might find that a brand doesn’t cater to your breast shape at all. For example, a UK lingerie brand may fit you differently than a US or Polish lingerie brand. This could be due in part to the bra shape, design, underwire, and overall fit of the bra, among other things.

Figure out your bra size and breast shape first

Some brands design for a more projected breast shape while others may design for a shallow breast shape. Others specialize in full bust styles and have a size run that starts at a D cup. This is why it’s important to become familiar with your bra size and breast shape and try on a bunch of different styles to find what works best for you.

Not sure where to start? We’d recommend starting with a trip to your local lingerie for a bra fitting if you’re not sure if you’re wearing the right bra size or if you have no idea what breast shape you have.

Already know your bra size and breast shape? Great! Read on to learn more about the differences between US and UK sizing (and be sure to check out our bra size conversion chart here if you’re ready to skip ahead!)

Related: The Complete Guide To Breast Shapes

US Sizing

First things first, the biggest difference between US and UK bra sizing is the lettering system. A US bra size chart looks like this:


UK Sizing

On the other hand, a UK bra size chart looks like this:

AA  A B  C D DD  E F FF G  GG H HH J JJ  K …

Note that the size chart starts to look different after a US DDD/F (which is equivalent to a UK E).

Key Points

Other than the differences in lettering, the sizing should be relatively the same (though it can vary brand to brand based on the brand’s fit). For example, if your US bra size is a 32DDD/F, you would find the best fit in a UK 32E. This is because a US DDD/F is equivalent to a UK E in terms of cup volume.


A UK H won’t fit you the same as a US H. In fact, the UK H would be equivalent to a US K and be way too big! If you’re shopping online for new bras, be sure to read about the brand so you know which sizing system they use. Alternatively, if you’re shopping at your local lingerie store, don’t be afraid to ask your bra fitter for help with converting your bra size to a UK or US brand.

No matter what, remember that the size on the tag is just a number and the fit of the bra is the most important thing. You can always cut out the tag, but you can’t easily adjust a bra if it’s not the right size or fit!

Ready to convert your bra size from UK to US sizing or US to UK sizing? Check out our helpful chart here.

Related: Find Your Perfect Fit With Our US To UK Conversion 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! 

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Published by

Katie Donnelly

Katie Donnelly is a full-time freelance writer, content manager, and founder of Katie Rose Creative. An experienced bra fitter, Katie has helped hundreds of people shop for lingerie. Her favorite bra is the Sandrine Plunge Longline Bra.

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