Are Bra Sizes The Same in the US and UK?

If you clicked on this article, you’re probably trying to get some help wrapping your head around all the different bra sizes you read about. Especially about US to UK bra sizes. Bra sizing has definitely been a hard topic to understand, which is the reason why a lot of women still tend to get the wrong size bra for themselves although they have known how to read the bra sizes.

When it comes to bra size, there are several bra sizing conventions that are used across the world, which are otherwise known as “bra charts”. Some of the regions that have their own sizing chart are American (US), British (UK), European (EU), Japanese (JP) and South Korean (KO). Today, we’re going to explain to you the difference between UK and US bra sizing for more accurate bra sister sizing since they are the two most common sizes used worldwide.

UK Bra Sizing System

The digits in this method, for the most part, correlate to our under-bust measurement in inches. According to the old approach, you had to multiply your under-bust measurement by 4 or 5 to get your British band size. This guideline may have worked in the past when bras were made of non-elastic materials, but bras today are made of mostly stretchy material, so nowadays you can actually not follow the rule and try a bra that is close to your actual measurement.

AAA, AA, A, B, C, D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, KK, L, LL, etc..

Are the cups in the British system. There isn’t a double for E, and I/II aren’t there.

Here are the couple of things we noticed from the UK bra system:

  • Cup sizes that are below A, will be labelled with adding more As at the back, and it is unusual to find bras with more than triple As.
  • Double D comes after D, and E, followed by F and double F. Notice that there is no double E. According to Bratabase, there aren’t any brands in the UK that sells double E cups
  • Starting from cup size F, all cups go by single letter then followed by double letter, although there is no letter I. We are not sure of the reason why, but assume that it is to avoid confusion between capital letter “i” and the small letter “L”.

The only point where the UK and US systems truly intersect is the D cup, which is a cup created for a person with a 19cm discrepancy between the band and the measurement around the breasts in both of them.

US Bra Sizing System

The US sizing is getting more unpopular because of their inconsistency among the brands in the US, thus making it more difficult for people to choose the right bra.

US implements almost the same sizing with the UK bra size, but because in US, brands have the freedom to set their own version of their cup measurement, the sizing are usually like this:

AA, A, B, C, D, DD, DDD, E, F, G, H, I …

AA, A, B, C, D, DD/E, DDD/F, G, H, I …

AA, A, B, C, D, DD, E, F, G, H, I …

AA, A, B, C, D, E, F, G, H, I …

As you can see, it is indeed a little confusing and the reason behind why some brands do not use DD or E is unclear.

Unlike the UK system, DDD cups are common in US sizing, as are no double cups (except DD) and there are I cups in manufacturers that dare to go that high. The majority of products that claim to use US sizing rarely reach above G cups.

One thing to keep in mind is that band sizes in the United States and the United Kingdom are the same. For example, a US 32 band is the same as a UK 32 band.

Since they don’t have a standardized size in the bra industry, the tightness or looseness with which a band is cut differs across UK and US manufacturers, even though the UK is more consistent across their bra companies in the country.

Here is the comparison side by side of the two countries bra size chart:

us to uk bra size
Image via Pinterest

As shown in the chart, American manufacturers simply cycle through the alphabet, using no more than DDD as a multiple letter method. In reality, certain companies in the United States (and many in Europe) may mark a DD as an E and a DDD as an F. Some US companies use UK size methods, which further complicates the process of purchasing a bra.

Our advice, if you’re planning to buy something online, the rule of thumb is to find out what size technique the manufacturer uses before placing an order. If you’re offline shopping, always take a look at the bra’s tag. These days, bras will display the UK, US and even other countries’ sizes. If you’re still having trouble, you can try to go to the manufacturer’s website to make sure of their measurements. Some companies even have a built-in size converter for bras.

The bra’s material also does make a difference between the same bra size. For instance, according to Bra Fittings By Court, Natori uses more soft and stretchy fabrics for their bras, so you’ll find that they often have a stretchier band. On the contrary, Wacoal uses a tighter cut and firmer materials for their products, so if the two brands were compared, you’ll find that a 32 band size is more loose depending on the brand.

If you still feel confused about all these numbers, you are always welcome to drop your question at the All Things Bras Instagram page DM, we are more than happy to answer you!