Before you buy a kit for the Sophie Swimsuit, you need to determine the underwire size we should include in the kit for you. You can do that in one of two ways: follow our guide below to find your suggested size based on your measurements, or choose a size based on your traditional bra size (suggested only if you are sure you are wearing the right sized bra!)

PLEASE SEE THIS POST IF YOU NEED TO GRADE BETWEEN SIZES OR INCREASE CUP SIZE.

Here's how to find your underwire size based on your measurements:

Full bust: Measure around your chest evenly at the fullest part of your bust with your arms down. Ensure the measuring tape is level across front and back.

Underbust: Exhale deeply and measure around your ribcage just beneath your breasts with your arms down. Pull the measuring tape somewhat taut.

Subtract your full bust from your underbust. The difference in inches is your cup size. Using the chart below, find your underbust size and your corresponding cup size. Where those two columns intersect is your suggested underwire size.

For example... If you have an underbust measurement of 34 and a full bust of 38, you would choose the 34" underbust (size 12) with the 4 cup. This would mean you require the #40 underwire.

If you are confidant you are wearing the right bra size, you can choose an underwire based on the size you usually wear.