The U.S. Department of Agriculture recommends baking chicken thighs in the oven for 40 to 50 minutes at 350 degrees Fahrenheit. Longer cooking times should be employed if the chicken thighs are heavier than 8 ounces.
The purpose of this cooking time and temperature is to raise the internal temperature of the chicken thighs to 165 F as recommended by USDA guidelines. This temperature ensures that the chicken is free of pathogens and is safe to eat. Baking at 350 F for at least 40 minutes usually brings chicken thighs to the proper internal temperature, but it is always a good idea to double-check the internal temperature with a meat thermometer to be sure.