How long do you cook a 20 pound turkey.?

For a 20-pound turkey, you should cook it for approximately 4 to 4.5 hours if roasting at 325°F (163°C). If the turkey is stuffed, it may take a bit longer, around 4.5 to 5 hours. Always use a meat thermometer to ensure the internal temperature reaches 165°F (74°C) in the thickest part of the turkey and the stuffing, if applicable. Let the turkey rest for at least 20 minutes before carving.