Most single breasted suits have two or three buttons, and one or four buttons are unusual. It is rare to find a suit with more than four buttons, although zoot suits can have as many as six or more due to their longer length.

There is also variation in the placement and style of buttons, since the button placement is critical to the overall impression of height conveyed by the jacket. The center or top button will typically line up quite closely with the natural waistline. Double breasted jackets have only half their outer buttons functional, as the second row is for display only, forcing them to come in pairs. Some rare jackets can have as few as two buttons, and during various periods, for instance the 1960s and 70s, as many as eight were seen.

Six buttons are typical, with two to button, which is the last pair floats above the overlap. The three buttons down each side may in this case be in a straight line or more commonly, the top pair is half as far apart as each pair in the bottom square. A four button double breasted jacket usually buttons in a square. The layout of the buttons and the shape of the lapel are co-ordinated in order to direct the eyes of an observer. For example, if the buttons are too low, or the lapel roll too pronounced, the eyes are drawn down from the face, and the waist appears larger.

The custom that a man's coat should button left side over right, anecdotally originates in the use of the sword, where such cut avoided catching the top of the weapon in the opening of the cloth since the sword was usually drawn right handed. Women's suits are buttoned right side over left. A similar anecdotal story to explain this is that women were dressed by maids, and so the buttons were arranged for the convenience of their, typically, right handed servants. Men on the other hand dressed themselves and so the buttons were positioned to simplify that task.

The jacket's lapels can be notched, peaked, shawl, or trick. Each lapel style carries different connotations, and is worn with different cuts of suit. Notched lapels are only found on single breasted jackets and are the most informal style. Double breasted jackets usually have peaked lapels. Shawl lapels are a style derived from the Victorian informal evening wear, and as such are not normally seen on suit jackets.

In the 1980s, double breasted suits with notched lapels were popular among the Power suit and the New Wave style. In the late 1920s and 1930s, a design considered very stylish was the single breasted peaked lapel jacket. This has gone in and out of vogue periodically, being popular once again during the 1970s, and is still a recognized alternative. The ability to properly cut peak lapels on a single breasted suit is one of the most challenging tailoring tasks, even for very experienced tailors.

The width of the lapel is a widely varying aspect of suits, and has changed widely over the years. The 1930s and 1970s featured an exceptionally wide lapel width, whereas during the late 1950s and most of the 1960s suits with very narrow lapels were in fashion. The 1980s saw mid size lapels with a low gorge, which is the point on the jacket that forms the notch or peak between the collar and front lapel. Current trends are towards a narrower lapel and higher gorge.

Lapels also have a button hole on the lapels, intended to hold a boutonniere, a decorative flower. These are now only commonly seen at more formal events. Usually double breasted suits have one on each lapel, while single breasted suits have just one on the left.