Recently, I was at a corporate dinner/dance and I was amazed at how some of the attendees did not know how to wear their suit jackets properly in different scenarios. There were lots of problems that caught my attention, but one of the specifics was the buttons on the attendees’ suit jackets.
Here are a few rules to consider:
1) Generally speaking, if you are standing, all of the buttons on your suit jacket, except for the bottom-most one, should be buttoned. If you are wearing a one-button suit, you would be a special case and you would simply always have your jacket buttoned up (while standing of course).
2) If you are sitting down (i.e. for dinner), then you should leave all of the buttons on your jacket unbuttoned. By no means should you take off your suit jacket. It doesn’t matter that you may feel warm. If you do feel warm, you should simply live with it and drink cold water 
– either that, or just buy a jacket that is made of lighter fabric.
3) For the dancing portion of the evening, there are a few conventions. If you are slow dancing, then you should keep your jacket buttoned (except for the bottom-most button). If you are dancing to more modern music (perhaps hip-hop), then you can unbutton your jacket. Generally speaking, you shouldn’t take off your jacket at any point in the evening. You might still take off your jacket if you get really warm, but if you can, keep it on – it looks more professional.
Bryan
March 2, 2011
8:04 am
Do the buttoned/unbuttoned rules apply to a suit with no tie?