What kind of suit you wear depends heavily on the event itself.
Choosing between a three-piece suit and a two-piece suit can be tricky. There really is no favoured look but you may want to bear in mind these factors before you decide.
Firstly, what kind of suit you wear depends heavily on the event itself.
If you are going to a formal event such as a dance or charity function, a day at the races or to the obvious one, of course, a wedding, then a three-piece suit is more appropriate.
A two-piece suit is better suited for interviews, meetings, dining out; anything that is not such a formal occasion.
This is only a rough guideline and really is up to you what one you choose. And if you are not sure, then it is always best to come over-dressed than under-dressed.