The centerpiece of contemporary Thanksgiving in the United States and in Canada is Thanksgiving dinner (informally called turkey dinner), a large meal generally centered on a large roasted turkey. Thanksgiving could be considered the largest eating event in the United States as measured by retail sales of food and beverages and by estimates of individual food intake. People often consume as much as three or four thousand calories during the course of the dinner.

Along with attending church services, Thanksgiving dinner remained a central part of celebrations from the holiday's early establishment in North America. In a 2015 Harris Poll, Thanksgiving was the second most popular holiday in the United States (after Christmas), and turkey was the most popular holiday food, regardless of region, generation, gender, or race. At Thanksgiving dinner, turkey is served with a variety of side dishes which can vary from traditional, such as mashed potatoes, stuffing, and cranberry sauce, to ones that reflect regional or cultural heritage.

Given that days of thanksgiving revolve around giving thanks, the saying of grace before Thanksgiving dinner is a traditional feature of the feast. Many of the dishes in a traditional Thanksgiving dinner are made from ingredients native to the Americas, including turkey, potato, sweet potato, corn (maize), squash (including pumpkin), green bean, and cranberry. The Pilgrims may have learned about some of these foods from Native Americans, but others were not available to the early settlers. The tradition of eating them at Thanksgiving likely reflects their affordability for later Americans. Early North American settlers did eat turkey, but the lavish feasts that are frequently ascribed to Thanksgiving in the 17th century were a creation of nineteenth-century writers who sought to popularize a unifying holiday in which all Americans could share.