FF Cup Bras – Brands That Make FF Cups & How to Find Your Size
A UK FF cup is often where bra sizing starts to feel confusing. Some brands include FF as part of an extended cup sequence, while others move straight from F to G. This guide explains what FF cup really means, which brands make it, and how to find the right fit.
To confirm your starting size, begin with our Bra Size Calculator, then use the brand guidance below to shop confidently.
Want to browse FF cup bras by band size? Visit our FF Cup Bras by Band Size page to jump straight to sizes like 32FF, 34FF, 36FF and more.
Who This Guide Is For
- Women who wear a UK FF cup
- Those moving up from F and unsure what comes next
- Shoppers confused by FF vs G sizing
- Anyone comparing traditional and extended UK cup sequences
- People struggling with inconsistent fit between brands
Why Not All FF Cup Bras Are the Same
The FF cup is part of the extended UK cup size sequence used by many fuller-bust bra brands. While FF is a recognised UK bra size, some brands use different cup lettering systems, which can make size comparisons confusing.
In extended UK sizing, FF sits between F and G. Some traditional cup sequences move directly from F to G instead, which is why checking the brand's sizing system is important when comparing bra sizes.
The FF cup is one of the double-letter sizes used in UK bra sizing. Double cups such as FF, GG and HH are additional cup size steps rather than half sizes. For a full explanation, see our Double Cup Bra Size Guide .
Many shoppers also compare neighbouring cup sizes. You can learn more in our F vs FF vs G Cup Size Comparison .
How Big Is an FF Cup?
A UK FF cup bra sits within the fuller-bust range of the UK cup size sequence. However, how large an FF cup appears depends on factors such as band size, body proportions and bra design.
For example, a 30FF and a 40FF do not have the same cup volume. Cup volume increases as band size increases, which is why the cup letter alone does not tell the full story.
If you would like to see visual examples across different band sizes, visit our How Big Are FF Cups? guide.
FF Cup Size Progression
An FF cup sits between F and G in the extended UK cup size sequence used by many fuller-bust brands. The diagrams below show how cup volume increases gradually while the band size remains the same.
FF sits between F and G in the UK bra size sequence.
These simplified educational diagrams show how cup volume increases across nearby UK cup sizes when the band size stays the same.
Cup volume increases gradually across the UK sizing system. A 34G has more cup volume than a 34FF, while a 34F has slightly less.
How cup sizes actually work: Bra cup sizes are based on a simple fitting rule — each step in the cup sequence represents a 1 inch difference between the bust and underbust measurement. This rule applies across all UK brands, regardless of whether they use a traditional or extended cup letter sequence.
In brands that use an extended UK cup sequence, FF is a separate cup size positioned between F and G. Each step represents the same one-inch increase in measurement difference, making FF one cup size larger than F and one cup size smaller than G.
The difference between brands is the lettering used, not the size step itself. For example, some traditional UK cup sequences move directly from F to G, while extended UK sizing includes FF as an additional cup size between them.
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 FF Cup the Same as a US FF 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 FF 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 cup size is not one fixed volume. Cup volume increases as the band size increases, so a 30FF, 34FF and 40FF are all very different in fit and capacity, even though the cup letter is the same.
Always consider both band size and cup size together when comparing bras.
UK Brands That Make FF Cup Bras
FF cup bras are typically found in fuller-bust specialist brands that use an extended UK cup sequence. The brands below have confirmed FF cup availability.
- Bravissimo – Bands 28–40, cups D–L View size guide
- Freya – Bands 28–42, cups B–K View size guide
- Panache – Bands 28–46, cups B–K View size guide
- Sculptresse – Bands 34–46, cups D–K View size guide
- Goddess – Bands 32–56, cups B–K View size guide
FF Cup Band Sizes by Brand
Based on confirmed brand availability tables, these are the UK band sizes typically available in an FF cup. Availability may vary by style.
- Bravissimo: 28FF, 30FF, 32FF, 34FF, 36FF, 38FF, 40FF
- Freya: 28FF, 30FF, 32FF, 34FF, 36FF, 38FF, 40FF, 42FF
- Panache: 28FF, 30FF, 32FF, 34FF, 36FF, 38FF, 40FF, 42FF, 44FF, 46FF
- Sculptresse: 34FF, 36FF, 38FF, 40FF, 42FF, 44FF, 46FF
- Goddess: 32FF, 34FF, 36FF, 38FF, 40FF, 42FF, 44FF, 46FF, 48FF, 50FF, 52FF, 54FF, 56FF
FF Cup Volume Changes With Band Size
Many people assume that all FF cups are the same size. In reality, cup volume increases as band size increases. A 38FF holds more volume than a 34FF, while a 30FF holds less.
The cup letter stays the same, but overall cup volume increases as the band size increases.
These simplified educational diagrams show how cup volume changes as the band size increases, even when the cup letter remains FF.
A bra size consists of both the band size and cup size. A 38FF holds more cup volume than a 34FF, while a 30FF holds less, despite all three using the same cup letter.
Popular FF Cup Bras (UK Sizing)
Below are selected FF cup bras in UK sizing from fuller-bust specialist brands. These examples show styles commonly available in FF cup sizes across a range of band sizes. If you are still confirming your size, see the fitting advice and sizing information further down this guide before purchasing.
As an Amazon Associate, we may earn from qualifying purchases. This does not affect the price you pay.
How to Find Your Correct FF Cup Size
Measure your underband and bust carefully, then enter your measurements into our Bra Size Calculator to get a recommended UK starting size.
For measuring tips and fit checks, see our Bra Fitting Advice.
Common Fit Issues for FF Cup Bras
- Band riding up at the back (often means the band is too big)
- Cups gaping (often shape-related, not always “too big”)
- Spillage at the top edge (often means the cup is too small)
- Wires sitting on breast tissue at the sides
- Straps digging in or slipping off
If your F cup fit feels inconsistent, try another style within the same brand or compare brands using our Bra Size Converter.
Can I Sister Size Instead of Wearing an FF Cup?
Sister sizing can help if your exact size is unavailable in a specific style, but it should be used carefully. If you go up a band size, you usually need to go down a cup size to keep a similar cup volume (and vice versa). However, sister sizes can change where wires sit and how the bra supports you, especially across different shapes.
FF Cup Sister Size Example
When sister sizing, the band size changes while the cup volume stays similar. A common FF cup example is:
These sizes have a similar cup volume, but different band lengths.
Sister Size Comparison
These diagrams provide a simplified visual example of sister sizing. While the band size changes, the overall cup volume remains broadly similar.
Sister sizes can help when your usual size is unavailable. As the band size increases, the cup letter decreases to maintain a similar cup volume.
For a full explanation of how sister sizing works, see our Bra Sister Sizes Guide .
Use our Bra Size Converter to compare UK brand sizing and sister sizes accurately.
Explore More FF Cup Guides
If you want to compare FF cup sizes in more detail, these related guides can help you understand cup volume, band size, sister sizing and neighbouring cup sizes.
- FF Cup Bras by Band Size
- How Big Are FF Cups?
- F vs FF vs G Cup Size Comparison
- Bra Sister Sizes Guide
FF Cup Bra FAQs
Is FF bigger than F?
Yes. In extended UK sizing, FF is one cup step larger than F and one step smaller than G.
Do all brands offer FF cups?
No. FF is mainly used by fuller-bust specialist brands that follow an extended UK cup sequence.
Does band size affect FF cup volume?
Yes. A 38FF holds more volume than a 32FF, even though the cup letter is the same.
FF cup sits between F and G in extended UK sizing. If you're deciding between sizes, it can help to compare F cup bras and G cup bras to find the best fit.
Related Cup Size Guides
For general background on bra sizing systems, see the bra size reference on Wikipedia .