Question 1

Why do UK bra cups use double letters after D?

Accepted Answer

British sizing keeps every half-step in the alphabet, so DD, FF, GG, and HH all exist. US charts collapse some of those steps into single letters like G or H, which is why you slide one letter back when converting.

Question 2

How can I tell if a bra already follows UK sizing?

Accepted Answer

Check the brand's origin and look for extra columns on the size label. If the tag highlights UK or UK/USA sizing separately, trust the UK column. Brands manufactured in the UK almost always use the British scale worldwide.

Question 3

Does converting the cup change the band fit?

Accepted Answer

No. Band numbers represent the same body measurement in inches across US and UK systems. Only adjust the band when you intentionally want a tighter or looser fit, then offset with the appropriate sister size cup.

Question 4

What if my converted UK size is hard to find in stock?

Accepted Answer

Search retailers that specialize in UK full-bust brands, or try the nearest sister size. For example, if 34FF is unavailable, test 32G or 36F to preserve cup volume.

US 34DDD (F) -> UK 34E

US 32G -> UK 32F

US 30H -> UK 30FF

US 38I -> UK 38G


AA	AA
A	A
B	B
C	C
D	D
DD	DD
DDD / F	E
G	F
H	FF
I	G
J	GG
K	H
L	HH
M	J
N	JJ
O	K
P	KK