A single-breasted suit includes a simple jacket or coat and a pair of formal trousers. On the other hand, a double-breasted suit consists of a double-breasted jacket and formal trousers. The cut and design of double-breasted suits define the body’s shape and therefore add a sharp touch to the overall look. That is why these suits are better options for formal occasions, whereas single-breasted suits are ideal for semi-formal or casual events.