Designed exclusively for fuller busts, the Signature Full Cup Bikini top combines our unique Core Swim Support System with considered fuller bust styling to deliver powerful, unwavering support and modern elegant style.

Clean, contouring lines and gently ruched cups create a naturally flattering silhouette, while the classic black colourway accented by luxurious golden trims elevates your look to create a timeless statement of style and sophistication.

Designed to outperform standard DD+ swimwear, this is support you can rely on—before, during, and after you swim.

When support is right, everything changes.
 - You move with ease.
 - You feel more secure.
 - You stop adjusting—and just enjoy.

The Core Swim Support System

Support sits at the core of every design with a discreet internal structure developed specifically for fuller-bust swimwear. 

Combined with principles of lingerie construction, it works beneath the outer fabric to stabilise, support, and maintain shape—even in water, where standard swimwear often loses structure.

By anchoring support through the band and internal construction, it reduces reliance on the straps and delivers consistent lift throughout wear. Considered performance for fuller busts, engineered into every piece.

The Black Signature Full Cup Bikini Top
A refined fuller-bust silhouette designed for secure support, effortless movement, and all-day confidence in and out of the water.

Ethically made in Europe using premium Italian eco-fabrics.

The key to your bikini doing what it has been designed to do is the fit. If it doesn't fit you properly, it won't support you properly.

The Core Bikini Top:

1. Back size:

The Core bikini top has been designed to be as close as possible to your bra size so you should order your standard back bra size (e.g. 36). Please note that the Core bikini has been designed to fit snuggly on your back size. We do not mean tight (that would be uncomfortable) but we do mean snug. The reason for this is:

1. A lot of the support from the bikini (and your every day bra) comes from the back. If the back is too big, you will lose support

2. Although the Core Swim bikini is fully lined (including the wings) to minimise stretch and maximise support when wet, we want you to be just as confident in your wet bikini as your dry bikini so we've designed it snug (again not tight!) so there is no need for those public adjustments when you get out of the pool.

Advice: If your bikini arrives and the back is not snug, consider a smaller size as you may get a better support. If it is too tight, please consider the next size up.

Note that if you size your back size up or down, you will also need to change your cup size to reflect this (it's called "sister sizing", see below).

2. Bikini cup size:

This is a sister sizing bra size chart and shows you the size you need to adjust to depending on the individual fit issue. For example, if you had a 36FF and the back was too tight but the cup fit, you would go up a back size and down a cup size to a 38F. Or, if the 36FF was too big on the back but fine in the cup, you would go down a back size and up a cup size to a 34G (see black arrows):

If the back fit you perfectly but the cup feels big then just go down a cup size to a 36F. Or, if the cup is not covering you as much as you would like or there is bulging, then go up a cup size to a 36G (see the red arrows).

 International Size Conversions:

Delivery Charges to UK

• Delivery is free for orders over £125
• The delivery fee for orders under £125 is £4.95 
• We use Royal Mail Tracked delivery service which will usually arrive within 2-3 business days from date of dispatch
  
• We do not currently offer next day delivery service
• We aim to dispatch orders within 2 working days. During busy promotional periods it may take longer to dispatch your order

International Delivery Charges

• USA - Standard International Delivery (3-7 days) = $30 USD
• Canada - Standard International Delivery (3-7 days) = $45 CAD
• Europe - Standard International Delivery (3-7 days) = £25 GBP 

International Duties and Taxes

All orders are shipped from the UK and may be subject to customs fees, import duties, and taxes once the shipment reaches your country. These charges are set and collected by your local customs authority and are outside of our control. Customers are responsible for paying any additional fees that may apply.

If you would like more information before placing an order, we recommend contacting your local customs office.

Returns Policy

• We want you to be completely happy with your Core Swim purchase but if you want to return it for any reason, then you can return it within 14 days of the date of delivery for a full refund (excluding any delivery charges)
• To start a return please sign into your account or follow this link Click here to start a return
• You must notify us of your intention to return within 14 days of receiving the item
• Once your return request has been confirmed, you have 14 days to return the item to us
• Returned items must be unused and unworn with hygiene stickers and security swing tags intact on the garments. Items we cannot resell due to damage whilst in your possession will not be refunded. Please return them in the same condition you would expect to receive them (be mindful of make-up, deodorant etc)
• Due to the nature of the products, all returned items are sanitised before being returned to stock and resold. A £2.50 fee will be deducted from your refund for this service. Note this cost is per order, not per item.
• The cost of return is at your own expense and will not be refunded unless the item is faulty
• Please retain a proof of postage with reference as we will be unable to issue a refund for goods that do not arrive back to us
• Once we receive your return we will issue a refund via the original payment method
• If you are returning items that received free UK shipping, a £4.95 charge will be deducted from your refund to cover the cost of the free shipping
• Your refund will be processed within 5 working days
  
• Click here to start a return

Exchanges - United Kingdom only

• If you would like to return any items for an exchange then please email us at sales@coreswim.co.uk or click reply on your order confirmation email
• Please quote your order number, details of the items you are returning and details of the items you wish to exchange them for
• We will check stock and confirm availability via email
• You must notify us of your intention to return/exchange within 14 days of receiving your order (as per the above returns policy)
• We must receive the returned items within 14 days of us confirming the exchange
• The cost of return is at your own expense. Please retain a proof of postage with reference as we will be unable to issue a refund or exchange for goods that do not arrive back to us
• Once received we will processs the exchange. If the cost of your exchanged items is less than your original items then we will refund the difference via your original payment method
• We offer FREE DELIVERY on exchanges on orders within the UK (one per order)
• This exchange policy only does not apply to items on sale or promotion 

Faulty Products

• Our products have been made by highly skilled seamstresses using only high quality materials and they have been put through rigorous quality control procedures
• We expect them to arrive with you in perfect condition and if cared for according to our care advice, to last you a long time.
• In the event that your product arrives faulty please contact us to arrange a return and refund
• In the event that your product develops a manufacturing fault after use, please contact us to discuss and to arrange a return. Please note that normal wear and tear is not considered a fault and we would expect that the garments had been cared for according to the care label instructions