Size conversion
What Is a 40B in Other Brands?
Bra sizes are not standardized: the same label means different things brand to brand, so your 40B is a starting point, not a fixed size. A US 40B usually needs a 40C in Victoria’s Secret, maps to a 40B in a true-to-size UK brand like Panache, and stays a 40B in Wacoal.
Your 40B in Victoria's Secret
40C
Cups run a full cup small, so size up
Your 40B in Panache
40B
True-to-size UK sizing
Your 40B in Wacoal
40B
True to size, year after year
Every brand we track
Your 40B, brand by brand
Grouped by the sizing system each brand labels its cups in. Brands we stock link to their full lineup.
US-sized brands
| Brand | How it runs | Your 40B → |
|---|---|---|
| ThirdLovein stock | cups run generous | 40B |
| Wacoalin stock | true to size | 40B |
| Glamorisein stock | true to size | 40B |
| SHEFITin stock | - | Adjustable XS-6Luxe sizing rather than standard band/cup; size by the brand chart. |
| b.tempt'din stock | true to size | 40B |
| Kindred Bravelyin stock | - | Uses XS-XXL nursing/maternity sizing rather than band/cup; size by the brand chart. |
| ENELLin stock | - | Uses numeric high-impact sizing (00-8) rather than band/cup; size by the brand chart. |
| Natori | cups run small | 40B |
| Bali | band runs large | 38B |
| Playtex | band runs large | 38B |
| Maidenform | true to size | 40B |
| Vanity Fair | band runs large | 40B |
| Calvin Klein | band runs small | 40B |
| Victoria's Secret | cups run small | 40C |
| Brooks | band runs small | 40B |
| Under Armour | - | Compression fit runs generous; XS-XL sizing rather than band/cup; size by the brand chart. |
| Nike | - | Generous fit; XS-XL sizing rather than band/cup; size by the brand chart. |
| Cacique | band runs large | 40B |
| Torrid | band runs large | 40B |
UK-sized brands (cups run D, DD, E, F, FF, G...)
EU-sized brands
| Brand | How it runs | Your 40B → |
|---|---|---|
| Chantelle | cups run small | 40B |
| Simone Perele | cups run small | 40B |
| PrimaDonna | true to size | 40B |
| Marie Jo | true to size | 40B |
| Triumph | band runs large | 40B |
| Anita | true to size | 40B |
Translations are guidance from cross-brand fit data, not a guarantee - fit also depends on breast shape and style. Cross-brand offset data v1-2026-05-28.
In stock now
Shop 40B now
Real bras we track in stock in 40B, with live prices.

Fantasie
Belle Balcony Bra: White

Fantasie
Belle Balcony Bra: Black

Elomi
Cate Non Wired Soft Cup Bra: Latte

Elomi
Cate Non Wired Soft Cup Bra: White

Elomi
Cate Non Wired Soft Cup Bra: Black

Panache
Power Wired Sports Bra - Marble

Panache
Non Wired Sports Bra - Black

Panache
Non Wired Sports Bra - Latte
40B sister sizes
Sister sizes hold the same cup volume on a different band. If the 40B cup fits but the band doesn’t, try:
Interactive
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Brand Size Translator
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Common questions
40B conversion questions
- What is a 40B in Victoria's Secret?
- Victoria's Secret cups run about a full cup small, so a standard US 40B usually needs a 40C there. If you already wear a 40B in Victoria's Secret, your size in a true-to-size brand is likely a cup smaller.
- Which brands keep a 40B the same?
- In true-to-size brands a US 40B stays a 40B: Wacoal, Panache, Glamorise, b.tempt'd, Maidenform, Fantasie, Gossard, Pour Moi, PrimaDonna, Marie Jo, Anita, Goddess. Fit can still vary by style, so treat the label as the starting point.
- Do UK brands size a 40B differently from US brands?
- UK brands label cups in a different sequence above D (D, DD, E, F, FF, G), so the same letters can mean different volumes. In a true-to-size UK brand like Panache, a US 40B is a 40B; the band number stays the same.
- What size replaces a 40B in brands that don't use cup sizes?
- SHEFIT, Kindred Bravely, ENELL, Under Armour, Nike size by their own charts (XS-XL or numeric) instead of band/cup, so a 40B doesn't carry over directly. Start from each brand's chart with your underbust and bust measurements.