I have to send this back.  I wear a 32c and a small was too big.  You can not go by cup size but by bust measurement.  An extra small is a 33" to 34".  The material is nice, it has those tiny pinholes so it will dry fast.  It appears well made.  If it had fit I would have gladly kept it.  According to the chart even an extra small will be too big.