Not all guys are aware of the fact that buttoning the bottom button of your suit coat is a big NO-NO! Actually, if you go back to the earlier part of the 20th century, this was not always the case. Prior to, it was a pretty common thing to see illustrations of men with every button of their suit coat fastened regardless to how many buttons were on the coat. It was not until King Edward VII started leaving the bottom of his suit coat unbuttoned simply because he had gained too much weight to keep it fastened. As a result, and to avoid offending the king, a new trend was created which has transcended into modern style etiquette today whereas men leave their bottom button unfastened.
You may wonder why this even matters. The answer to that would be that when applying this simple rule to the way you wear your suit coat/blazer, it automatically communicates to others that you are the type of gentleman that pays attention to detail and one who is well-accustomed to suit-wearing. Since its all about presentation, these small strides toward improving your presentation can go a long way. Below are visual examples and rules of how this button game works:
On a one-button suit, the button is to always be fastened when standing.
Be sure to always unbutton your suit coat when seated as to not to ruin the coat. The strain from moving while seated with a buttoned suit, can eventually distress the garment as well as the sewing to the buttons.
On a two-button suit, the top button is to remain fastened while the bottom button is left undone.
When wearing a three-button suit, there are a few options... 1 - You can fasten the top two buttons and leave the bottom button unfastened or, 2 - You can simply button the middle button by itself.
Double-breasted suits should have all buttons fastened except for the bottom button.
As opposed to single-breasted suits, you can leave this guy fastened at the top button when seated. Reason being, when unfastened and seated, the extra flap in front appears sloppy and unattractive.
When wearing a vest solo, it is perfectly acceptable to have all buttons fastened and optional to have the bottom button unfastened.
When the vest is worn with a suit coat, the vest should always have all buttons fastened.
DRESS LIKE A GENT