How to...
Choose a Swimsuit Size?

When you’re fuller busted it can be tricky finding a one-piece swimsuit that fits – many of us find we need to size up to get enough room in the bust that leaves the waist and hips baggy, or we go for our normal size and have to deal with quad-boob, overspill, and the risk of a wardrobe malfunction! Not what we want when we’re trying to enjoy our holidays or go for a swim, which is why Brastop offers such a great range of swimsuits in cup and back band sizes.

Here we’ll go through how swimsuit sizing works, and give you guidance on choosing the right swimsuit size for you and your DD+ boobs.

How does bra-sized swimsuit sizing work?

Swimsuits that are bra-sized are arguably the best option for those of us who are more blessed in the chest. By shopping for your back and cup size, you know you’ll be getting that all-important support and a great fit to avoid the wardrobe malfunctions we mentioned before! But how does it work, and how do you know the rest of the suit will fit your body? Here’s how:

Fuller bust swimsuits that are sized by bra size are designed to fit the average body size of someone who wears that back band size. For example, if you wear a 30 back band bra you’re likely to be around a UK size 10-12. Those who wear a size UK 20-22 in clothes are more likely to be around a 40 band in their bras. Of course we’re all uniquely built so this isn’t a hard-and-fast rule, but it is a good guideline if you’re really unsure.

So, the top bra-sized portion of a swimsuit will be made to fit just like your regular bra in that size, while the body part will be structured and designed to fit across a couple of clothes sizes to get the most accurate fit possible across the entire swimsuit – no gaping bottoms or quad-boob here, thank you very much!

Do I need to choose a different size to my normal bra size?

In general, most people will find their standard bra size translates to a good fit in cup-sized swimsuits too. However, if you have a more dramatic waist-to-hip ratio then you might prefer to sister size up in a swimsuit to get a little more room and a comfortable fit across the hips and bottom.

Remember that swimwear fabric will generally feel a little snugger than your regular clothing and lingerie – this is because it needs to maintain its shape while wet, and it will stretch out a bit in the water.


"Very good fit and comfortable. Love that it has removable straps and an extra strap for low back tops."

Curvy Kate Superplunge Multiway Padded Plunge Bra

Step 1: Find a brand that makes bra sized swimwear

Take all the pain out of swimsuit shopping by finding brands that offer one-piece options in bra sizes. At Brastop, the majority of our swimwear is sized by band and cup so you can be sure you’re going to get the perfect fit and support for your bust! From brands like Curvy Kate, Parfait, Flirtelle and more we’ve always got a range of bra-sized swimsuits in stock.

Step 2: Work out your bra and swimsuit size

If you aren’t already sure of your bra size, now is the time to find out! Take our quick bra fit quiz to see if you’re in the right size for you, or get in touch with us for expert fitting advice.

Step 3: Shop for your swimsuit

This is the fun bit – shopping time! Head to our swimsuits collection to see everything we have available. Use the filters to shop by size, style and brand to find something that ticks all your boxes.

Step 4: Receive your swimsuit

Once your swimsuit arrives in the post, try it on and see how it feels! If it feels too firm in the band or too snug in the body, try re-ordering in your sister size up (up a back size, down a cup size e.g. 32F to 34E) for a more comfortable fit. Likewise, if it feels a bit too loose, try a sister size down (down a back size, up a cup size e.g. 36H to 34HH) for a snugger fit in the body.

So there’s our guidelines on how to find the right size swimsuit for you! Don’t forget we’ve got fuss-free 90 day returns so you can shop with total peace of mind in knowing that if you’re not happy with an item or want to return it for any reason, we’ll refund it for you as long as its unworn with tags attached.

Shop our beautiful D+ cup sized swimsuits, all year round:

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