A question that many travelers have is How To Add TSA Precheck To Lufthansa Airlines? Prior to adding TSA PreCheck to your Lufthansa reservation, confirm that your Known Traveler Number (KTN) is active. Once you have logged into your Lufthansa account, navigate to your profile or booking details. Enter your KTN in the passenger information section. Provide your KTN while booking a reservation over the phone or through an agent in order to qualify for TSA PreCheck.