Slim Fit Suit Size
most of the European Cuts Suits and sport coats in slim fit sizes will have same size of the blazer/sport coat as the trouser, but here will explain the easiest way to find out your right size.
You need to know your trouser size (waist), we mean by that the most recent time you measured your trouser waist, Jeans waist size are different because most cases Jeans fabric stretches and trousers mostly don't.
if your US trouser waist size is 32 for example, just add 16 and you will know your EU blazer / sport coat size, in all EU suits will Find size 48 suit has size 32 trousers. and in most cases you wont see size 32 on pants but you will see same EU size blazer on the trouser which is 48 in our example.
32+16= EU48 Suit
Another way to find out your EU slim fit Suit Size if you already know your US size slim fit blazer, simply, add 10 to your US Slim Fit Blazer Size and you will know your EU slim fit Suit Size, Example
US Slim Fit Suit 42 = EU Slim Fit Suit 52
this is a quick overview of the Slim fit suit sizes differences, we always recommend visit your local tailor and get the most accurate measurements.