One overlooked aspect of pizza ordering is the pizza recipe style. If you stick to a pizza recipe style that fills you up longer, you and your guests may need fewer slices. If you pile on the toppings or make the crust thick, some guests may only need one or two slices. Thin crust pizzas aren’t very filling, so you’ll need to order more than usual. You should order a little less of the deep dish or other thick crust pizzas.