It is very embarrassing when you go out to dinner with someone to a 5 star restaurant and they are wear shorts and a low cut tank top. 5 stars means it has been rated that highly for a reason. So dress highly. No jeans, no shirts showing your belly- instead dress classy and sophisticated. If your going to spend $200 on dinner- then dress like it. A fancy/classy restaurant is a place to show people how well mannered you are. Stick to a semi-formal, cocktail and black tie dress code.
What to Wear to a 5 Star Restaurant:
What Not to Wear to a 5 Star Restaurant: