What Is a Known Traveler Number?
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A Known Traveler Number, or KTN, is a 9-digit ID issued when you enroll in TSA PreCheck or a program like Global Entry. You enter it when booking a flight so the PreCheck indicator appears on your boarding pass and you can use the expedited security lane.
A Known Traveler Number is the key to actually using TSA PreCheck, but travelers often mix it up with other numbers or forget to add it. Here is what a Known Traveler Number is, where you get one, how to use it, and how it differs from a redress number.
What is a Known Traveler Number?
A Known Traveler Number, commonly abbreviated KTN, is the identification number assigned to you when you are approved for a trusted-traveler program, and it is what unlocks TSA PreCheck on your flights. It is typically a nine-digit number, though the format can vary slightly by program. The KTN links your reservation to your trusted-traveler membership, telling the airline and TSA that you are pre-approved for expedited screening. Without adding your KTN to a booking, you will not get PreCheck on that flight even if you are a member, which is why the KTN matters so much. In short, being enrolled gives you the benefit, but entering your KTN when you book is what actually delivers it.
Where do you get a Known Traveler Number?
You receive a KTN by enrolling in and being approved for a trusted-traveler program. If you sign up for TSA PreCheck directly, you are issued a KTN once approved, usually within a few days. If you enroll in Global Entry, which includes PreCheck, your membership comes with a PASS ID, and that number, found on the back of your Global Entry card, serves as your KTN. Members of other Department of Homeland Security trusted-traveler programs like NEXUS and SENTRI also use their PASS ID as a KTN. If you forget your number, you can look it up through the Trusted Traveler Programs website or your TSA PreCheck enrollment account. Keep your KTN handy, since you will reuse it for every booking.
How do you use your Known Traveler Number?
To benefit from your KTN, you enter it in the Known Traveler Number field when booking a flight or in your reservation details, and the smartest move is to save it in each airline's frequent-flyer profile so it is added automatically to every booking. When your KTN is correctly attached to a reservation, the PreCheck indicator, often the words TSA PreCheck, prints on your boarding pass, and only then can you use the PreCheck lane. Double-check that your name and date of birth on the booking exactly match your trusted-traveler enrollment, since a mismatch can cause the KTN not to work. If PreCheck does not appear on your boarding pass, verify your KTN was entered correctly before heading to the airport.
What is the difference between a KTN and a redress number?
They are two different numbers that serve opposite purposes, and it is easy to confuse them. A Known Traveler Number is a benefit: it identifies you as a pre-approved trusted traveler so you can access expedited PreCheck screening. A redress number, by contrast, is a fix: it is issued to travelers who have been repeatedly misidentified or delayed at security, often because their name resembles one on a watchlist, to help distinguish them and prevent those mix-ups. You add a KTN to get faster screening, and you add a redress number to avoid being wrongly flagged. Both have their own fields when booking, so enter each in the correct one, and do not put a redress number where a KTN belongs or vice versa.
A Known Traveler Number, or KTN, is the ID issued when you enroll in TSA PreCheck or Global Entry, and you add it to flight bookings so PreCheck appears on your boarding pass. Save it in your airline profiles so it applies automatically. It differs from a redress number, which fixes repeated misidentification rather than granting faster screening.
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