KK Cup Bras – Brands That Make KK Cups & How to Find Your Size
Finding well-fitting bras in a UK KK cup is extremely challenging, as very few brands manufacture cups at this level. This guide focuses specifically on KK cup bras, explaining which brands make them, how sizing works at this level, and how to confirm your correct size before buying.
To confirm your starting size, begin with our Bra Size Calculator, then explore the specialist brands listed below.
Who This Guide Is For
- Women who wear a UK KK cup
- Those sized out of most high-street and DD+ brands
- Customers needing maximum cup depth and support
- Shoppers comparing extended-size specialist brands
- Anyone repeatedly sister-sized due to limited availability
Why KK Cup Bras Can Still Fit Differently
Although KK cup is a recognised UK bra size, it sits within a much narrower part of the sizing system than smaller cup sizes.
Up to K cup, different UK cup letter sequences may be used by different brands. However, KK, L and LL cups are only produced using the extended UK cup sequence. Traditional UK sizing systems and retailer-specific variants do not extend to these sizes.
As a result, a KK cup represents the same step in cup volume across all UK brands that make it. There is no alternative “traditional” KK cup with a different volume.
This does not mean that all KK bras fit the same. Cup volume still increases as band size increases, and differences in wire width, cup depth, fabric strength and construction can significantly affect fit.
At KK cup level, finding the right bra depends less on letter interpretation and more on choosing the correct band size, brand and cup shape.
Why KK Cup Bras Are So Hard to Find
KK cup bras sit at the very top of the UK size range and are produced in extremely small volumes. Only a handful of specialist brands design patterns, underwires and support structures suitable for this cup depth. As a result, availability is limited by both cup size and band size, and many retailers do not stock KK cups at all.
If you wear a KK cup, it is especially important to focus on correct measurement and brand-specific size charts rather than relying on sister sizing or trial-and-error purchasing.
How Cup Sizes Are Actually Measured
All UK bra sizing follows the 1-inch rule, meaning each step in the cup sequence represents a 1-inch increase in the difference between the underband and the fullest bust measurement.
Fuller-bust brands use an extended UK cup sequence that includes additional double-letter cups:
D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, KK, L, LL
In this sequence, each cup step increases evenly by one inch. A KK cup sits one cup size above K and one cup size below L.
Differences between brands at this level are usually due to availability and design, not differences in how cup sizes are measured.
The KK cup is one of the larger double-letter sizes used in the UK bra sizing sequence. Double cups such as FF, GG, HH, JJ and KK represent additional steps in the cup progression rather than half sizes. For a full explanation of how these double-letter cup sizes work within the UK system, see our Double Cup Bra Size Guide .
UK vs US Bra Sizes
Bra sizing systems vary slightly between regions. Most specialist fuller-bust brands such as Panache, Freya, Fantasie and Elomi follow the UK cup size sequence, which includes double letters such as FF, GG and HH.
Some US brands use a slightly different lettering system, which can create confusion when comparing sizes internationally. To understand how the sizing systems relate, see our UK vs US bra size comparison guide .
Is a UK KK Cup the Same as a US KK Bra Size?
It depends on the brand. Many UK-based fuller-bust brands such as Panache, Freya and Elomi use the same extended UK cup sequence internationally, meaning an KK cup is labelled the same in both the UK and US.
However, some US lingerie brands follow a different cup progression. For this reason, always check the brand’s stated sizing system rather than relying on the cup letter alone.
A KK cup is not one fixed volume. Cup volume increases as band size increases, so a 32KK, 38KK and 42KK are all very different in fit and capacity.
Always consider both band size and cup size together.
UK Brands That Make KK Cup Bras
- Bravissimo – Bands 28–40, cups D–L View size guide
- Elomi – Bands 32–46, cups D–LL (limited extended styles) View size guide
- Royce – Bands 28–48, cups DD–L (wire-free & specialist styles) View size guide
KK Cup Band Sizes by Brand
- Bravissimo: 32KK, 34KK, 36KK, 38KK, 40KK
- Royce: 32KK, 34KK, 36KK, 38KK, 40KK, 42KK
- Elomi: 32KK, 34KK, 36KK, 38KK, 40KK, 42KK
Related Cup Size Guides
For background on UK bra sizing systems and cup progression, see the bra size reference on Wikipedia .