Fact or fiction: Going up a cup and down a band size is the same size
Does sister sizing work?
Yes, it works! Sister sizing, or the concept that going up a cup size and down a band size is the same size bra, really works. Find a really cute bra, but it’s not your size? Don’t worry you might be able to get away with a different size. In the cup size game, a 32D is the same size as a 34C and a 36B. As you go up in bra sizes, it’s easier to find a closer match, and maintain your best fit.
Why does this work? Well, cup sizes are relative to the band that they are on. Therefore a C cup on a 34 band is not the same as a C cup on a 38 band. Each cup size accounts for a one inch increase in your bust line, or your body’s circumference, and as this is true it would make sense that as the cup size gets larger, the band size decreases because the cup adds an extra inch.
Be careful! While this is true, it is important to wear your true size when possible. You always want to have the best fit possible to support your girls. While this works across most brands, all bra companies have different fits, so check to make sure you are getting the best bra for you.
We want to hear from you! Send us your weirdest body questions here (seriously, we'll answer anything!) and it just might get featured.