Suit and Sports jackets should fit properly!!
Suit and Sports jackets are symbols of authority. However the bottom buttons of men’s jackets are not designed to be buttoned.
Single Breasted suits can have one, two, three or more buttons. Two and three button jackets are classic, one or more than three get you into the fashion forward arena, which is more suitable for social events than business. With two button jackets only the top button is fastened.
With two button jackets, you can close the top, and leave the bottom open. Some suits are made so that the lapels roll to the middle button. On those suits you leave the top button unfastened. Some East Coast hipsters fasten only the top of three buttons!
Four or more button jackets may be designed to fasten all the buttons, even the bottom. If the bottom button of a four button can be closed without a noticeable pulling of the fabric, it’s OK to close or leave it open.
Double Breasted suits are the more formal of the two styles and can have four to six buttons with one or two “to button.” They are often identified by a two-number designation such as 4/2, 4/1 or 6/2 (also “four to two”).
Translated, the first number gives the total number of front buttons and the second is the number of functioning buttonholes. It doesn’t always mean that all the buttons have to be fastened