For a buffet, it is recommended to have more plates than guests. Guests often go back for seconds and might prefer a fresh plate for different courses. Having extra plates handy is also useful in case of accidents or unexpected guests.

Generally, 1.25 plates per guest will suffice for smaller buffets (1.25 plates x 100 guest = 125 plates). However, larger buffets with multiple main courses and sides would require more plates, 2 to 2.5 plates per guest (2 plates x 100 guest = 200 plates or 2.5 plates x 100 guest = 250 plates).