👙 Bra Size
40C Bra Size — UK, EU & French Conversion
A US 40C bra in UK, European and French sizing, with its sister sizes. Not sure 40C is right? Measure with the bra calculator first.
US 40C = UK 40C
EU 90C · French 105C
A US 40C bra converts to UK 40C, EU 90C and French 105C. The band number maps on a fixed scale, while cup letters shift between systems above D.
| Region | Size |
|---|---|
| US | 40C |
| UK | 40C |
| EU (Europe) | 90C |
| FR / ES (France, Spain) | 105C |
Sister sizes for 40C
Same cup volume, different band — try these if the band feels tight or loose but the cup is right:
38DSister down
42BSister up
⚠️ US cup lettering above D varies by brand (DD vs E, DDD vs F). Match by the EU/UK equivalent when a brand's letters differ.
All bra sizes → · Bra calculator → · Converter →
What is a US 40C bra in UK and EU sizing?
A US 40C is a UK 40C, EU 90C and French 105C.
What are the sister sizes of 40C?
Same cup volume, different band: 38D, 42B.
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