When is it customary to cut the cake? The best time to cut the cake is shortly after your guests have finished their meal, but before the dancing begins. Cutting the cake is the segue from the more formal dinner reception to the more relaxed dancing reception. Your DJ will announce that the couple is about the cut the cake and usually a little crowd will form around the cake table.
Usually older guests or guests with young children will use dessert as a great ending to the wedding and quietly excuse themselves for the evening. The remaining crowd has closed out their meal with a tasty dessert and are ready to get started with a night of dancing! This is why it's best to not wait too long after dinner to serve the cake, but make sure your guests have had plenty of time to finish their meal.