👙 Bra Size
40A Bra Size — UK, EU & French Conversion
A US 40A bra in UK, European and French sizing, with its sister sizes. Not sure 40A is right? Measure with the bra calculator first.
US 40A = UK 40A
EU 90A · French 105A
A US 40A bra converts to UK 40A, EU 90A and French 105A. The band number maps on a fixed scale, while cup letters shift between systems above D.
| Region | Size |
|---|---|
| US | 40A |
| UK | 40A |
| EU (Europe) | 90A |
| FR / ES (France, Spain) | 105A |
Sister sizes for 40A
Same cup volume, different band — try these if the band feels tight or loose but the cup is right:
38BSister down
42AASister 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 40A bra in UK and EU sizing?
A US 40A is a UK 40A, EU 90A and French 105A.
What are the sister sizes of 40A?
Same cup volume, different band: 38B, 42AA.
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