Cooking raw chicken in a slow cooker on high typically takes about 3 to 4 hours for boneless, skinless chicken breasts to be fully cooked to a safe internal temperature of 165°F. Whole chicken or bone-in pieces may take a bit longer, around 4 to 6 hours on high. It is essential to use a meat thermometer to ensure the chicken is cooked through but not overcooked and dried out. Cooking chicken on low for a longer period (6 to 8 hours) is often recommended for juicier results, but high setting for 3 to 4 hours is common for quicker cooking.
