At participating airports, Southwest Airlines offers TSA PreCheck to qualified travelers, enabling a quicker and more convenient security process. Southwest TSA PreCheck you can leave laptops and liquids in your carry-on and wear your shoes, belt, and light jacket when using TSA PreCheck. You must apply, have your background checked, and get a Known Traveler Number (KTN) before you can use TSA PreCheck. If you want to be sure that your TSA PreCheck status shows up on your boarding pass, add your KTN when making your Southwest reservation. This facilitates faster and more efficient airport travel by giving you access to designated security lanes.