We have written a whole tipping guide just for weddings because there are so many people involved in the event, including florists, caterers, photographers, hair and makeup experts, bartenders and more. A good rule of thumb when you are planning a wedding is to include tip money for the vendors. When you are looking at the contracts, check the catering and bartending ones to see if there is a gratuity included, so you don't inadvertently double tip. Otherwise, tip 15-20%, to be split up among the workers.