The best way to ensure that your turkey is properly cooked is to use a meat thermometer inserted in the inner thigh. Your turkey is done when the temperature reads 82°C (180°F) for a stuffed turkey and 77°C (170°F) for an unstuffed turkey.
As an approximate guide for unstuffed (add an extra ½ hour for stuffed)
Oven Temperature 160°C (325°F)
Turkey Size: Time
8 – 10 lbs (3.5 – 4.5kg): 2 ¾ –3 hrs
10 – 12 lbs (4.5 – 5.5 kg): 3 – 3 ½ hrs
12 – 16 lbs (5.5 – 7.5 kg): 3 ¼ – 3 ½ hrs
16 – 22 lbs (7 – 10 kg): 3 ½ – 4 hrs
Please note that cooking times depend on the calibration of your oven. Remember too, that heat is lost every time you open the oven door and may slow the cooking time.
Health Canada recommends to cook your stuffing separately.