A Christmas sandwich or Christmas dinner leftovers sandwich (also , ), also known as a Boxing Day sandwich, is a sandwich made of leftovers from Christmas dinner. Popular in the United Kingdom as a seasonal meal, a Christmas sandwich can incorporate various traditional Christmas dinner foods, including Christmas ham, roast turkey, stuffing, and cranberry sauce.
In the 21st century, Christmas sandwiches have become a regular seasonal offering at sandwich shops and chain stores in the UK. In November 2024, a multi-day 'Christmas Party' food festival was held in Peckham, London.