Cooking a turkey overnight at 200 °F (about 93 °C) is not considered safe by food-safety authorities. The USDA advises against cooking any meat or poultry in an oven set below 325 °F (163 °C) because the food can stay too long in the “danger zone” between 40 °F and 140 °F, where bacteria can grow and some toxins may not be destroyed even if you later raise the temperature.

Food safety guidance

• USDA guidance states that whole turkeys should be cooked in an oven set to at least 325 °F and reach an internal temperature of at least 165 °F in the thickest parts to be safe to eat.

• Cooking methods that keep the oven around 190–200 °F for many hours are specifically flagged as unsafe because the turkey warms too slowly, increasing risk of harmful bacterial growth and toxin formation.

What to do instead

• If you want an overnight or “low and slow” method, use a recipe that starts hotter (for example 400–450 °F) and then drops to a moderate temperature that still keeps the bird heating quickly enough, always checking internal temperature with a meat thermometer.

• For safety, keep stuffing out of the turkey, cook the bird until all parts reach at least 165 °F, and hold it at 140 °F or above if you need to keep it warm before serving.