Turkey Breast Roasting Times Seasoned Insight > Turkey Tips > Turkey Breast Roasting Times Roasting times may vary greatly, depending on a number of variables that affect the cooking time such as the shape of the turkey breast, the proportion of meat to bone, the variations in different ovens, the altitude, and if the turkey is fresh or frozen and then thawed. Adding the confusion is that almost every source providing roasting times is different from one another. Listed below are roasting times that can be used as a general guideline. However, the only true gauge for determining proper doneness is with a meat thermometer. The breast must reach an internal temperature of 170°F. A shallow baking pan will yield the best results when roasting a turkey breast, allowing air to flow completely around the turkey breast.