Check in now for your American Airlines Flight! Get all the information you need about our check-in policy. We will show you how to check in online via mobile check-in or self-service check-in. Read about check-In times and boarding times of American Airlines. Learn more about the rules of American Airlines Flight Check-In and procedures. Visit our website to learn more about other airline policies of American Airlines; call us at +1-888-982-1907.