UK bra cup sizes progress from smaller single-letter cups through a sequence that includes both single and double letters. This guide brings together our individual UK bra cup size guides from AA through to LL.
Use the guides below to explore individual cup sizes, understand how cup volume changes across different band sizes and find related bra size tools and buying guides.
If you are unsure of your current size, measure your underbust and fullest bust and enter them into our Bra Size Calculator.
These guides explain how UK cup sizes progress and how band size and cup size work together:
In this UK cup-size guide, the sequence runs from AA at the smallest end of the range through to LL at the largest end.
This guide covers the complete UK bra cup-size range from AA to LL and links to a dedicated guide for each cup size.
A bra size combines a band size with a cup size. The cup letter represents one step within the UK cup progression, but it does not represent one fixed cup volume on every band size.
As the band size changes, the cup volume associated with the same cup letter also changes. This is why a 32F and a 38F do not have the same cup capacity even though both use the letter F.
UK sizing also includes several double-letter cup sizes. These are separate cup steps within the sequence rather than alternative names for the neighbouring single-letter size.
Because cup volume changes with band size, nearby band-and-cup combinations can sometimes have a similar cup volume. These are known as bra sister sizes.
For a visual reference, see our UK Bra Cup Size Chart.
A cup letter should always be considered together with its band size. The same cup letter represents a different cup volume when paired with a different band.
Buying guides are currently available for UK cup sizes from AA through J. Choose your cup size below to browse the published band-size guides and find the page for your exact UK bra size.
If you are unsure of your current bra size or want to compare nearby sizes, use the tools below alongside the cup-size guides above.
Enter your underbust and fullest bust measurements to calculate a recommended starting UK bra size.
Calculate Your Bra Size →Find nearby band-and-cup combinations with a similar cup volume to your current bra size.
Find Sister Sizes →Compare bra sizes across different sizing systems and participating lingerie brands.
Compare Bra Sizes →Learn how to measure your underbust and fullest bust and check the band, cups, straps, centre gore and underwires.
Check Your Bra Fit →Measure your underbust snugly and your fullest bust without compressing the breast tissue, then enter both measurements into the Bra Size Calculator.
The UK cup-size progression covered in this guide is AA, A, B, C, D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, KK, L and LL. Double-letter cups such as DD, FF and GG are separate steps within the sequence.
No. Cup volume changes with band size, so the same cup letter represents a different cup capacity when paired with a different band. For example, a 32F and a 38F are not the same cup volume.
Double-letter cup sizes are individual steps within the UK cup progression. They are not simply another way of writing the neighbouring single-letter cup. Read our Double Cup Bra Sizes Explained guide for more detail.
Measure your underbust snugly and your fullest bust without compressing the breast tissue, then enter both measurements into our Bra Size Calculator. The result provides a recommended starting UK band-and-cup size.
Sister sizes are different band-and-cup combinations with a similar cup volume. When the band size changes, the cup letter changes in the opposite direction. Use our Bra Sister Size Calculator to compare nearby sister sizes.
No. UK, US and European sizing systems use different cup labels and progressions. Use our Bra Size Converter when comparing sizes across different sizing systems.
Continue with these guides if you want to explore cup sizes visually, compare sister sizes or understand how UK bra sizes relate to one another.
See the complete UK cup progression from AA to LL and how cup size changes across different band sizes.
View the Cup Size Chart →Learn where double-letter sizes such as DD, FF, GG and HH appear in the UK cup sequence.
Understand Double Cups →Understand how different band-and-cup combinations can have a similar cup volume.
Explore Sister Sizes →Compare illustrated UK bra sizes side by side to see how band size and cup volume change together.
Compare Bra Sizes Visually →Measure your underbust and fullest bust, calculate your recommended UK bra size and then use the cup-size guides above to learn more about your result.
Start with the Bra Size Calculator, compare nearby sizes with the Bra Sister Size Calculator, and use our Bra Fitting Advice to check how the bra fits when worn.
