Where to find your TSA Known Traveler Number
Your TSA Known Traveler Number (KTN) is a nine-character code assigned to you when you enroll in TSA PreCheck or another trusted traveler program. You can find it in three places: your enrollment confirmation email, your TSA PreCheck card itself, or your account on the TSA website.
The easiest route is to check your email. When TSA approves your enrollment, they send a confirmation message that includes your KTN in the body of the email or as part of your approval notice. If you still have that email, search for "KTN" or "Known Traveler Number" and you'll see the nine-character code clearly labeled.
If you have your physical TSA PreCheck card, the KTN is printed on the front of the card, usually in the upper right corner or along the bottom edge. The number appears as a sequence like "ABC123DEF4"—nine characters mixing letters and numbers.
For a digital lookup, log into your account at tsa.gov/precheck using your login credentials. Once you're in your account dashboard, your KTN will be visible on your profile page or in your enrollment details section.
Key Takeaways
- Your TSA Known Traveler Number is a nine-character code that appears on your TSA PreCheck card, in your enrollment confirmation email, and in your online account at tsa.gov/precheck.
- The fastest way to locate it is to search your email for the word "KTN" in your original approval message from TSA.
- If you have your physical card, the number is printed on the front, usually in the upper right or bottom section.
- You need your KTN when you book flights so the airline can link it to your reservation and give you TSA PreCheck screening.
How to add your KTN when booking a flight
Once you have your KTN, you enter it into your airline reservation so TSA PreCheck screening is applied to your boarding pass. Most airlines have a field labeled "Known Traveler Number," "KTN," or "Trusted Traveler Number" during the booking process on their website or app.
Add your KTN at the time you book your ticket, or go back into your reservation afterward and edit your passenger details to add it. If you forget to add it before your flight, you can usually still add it up to 24 hours before departure by logging into your airline account and updating your reservation.
Some airlines also let you save your KTN in your frequent flyer profile so it automatically fills in every time you book. Check your airline's website under "Trusted Traveler" or "PreCheck" settings to see if this option is available.
What happens if you can't find your KTN
If you've lost your card and can't locate your confirmation email, you can request your KTN directly from TSA. Call the TSA PreCheck customer service line at 1-855-347-8371 during business hours, and they can look up your number using your name and date of birth.
You can also submit a request through the TSA website by logging into your account and looking for a "Contact Us" or "Help" section. Response times vary, but email requests typically get answered within a few business days.
If your TSA PreCheck enrollment has expired and you need to renew it, you'll receive a new KTN when your renewal is approved. The renewal process is similar to the initial enrollment and takes about the same amount of time.
Why your airline needs your KTN
Airlines use your KTN to connect your TSA PreCheck status to your boarding pass. Without it linked to your reservation, the TSA screening officers at the airport won't know you're enrolled in the program, and you'll go through standard security screening instead of the faster PreCheck line.
The airline doesn't verify your KTN—they straightforward pass it along to TSA. TSA's system checks whether the number is valid and active, and if it is, your boarding pass will print with a TSA PreCheck indicator (usually a checkmark or the words "TSA PRE✓").
If you enter an incorrect KTN, your boarding pass won't show the PreCheck indicator, and you'll miss out on the expedited screening benefit. That's why double-checking the nine-character code before you submit your reservation matters.
KTN for other trusted traveler programs
If you're enrolled in Global Entry, NEXUS, or SENTRI instead of TSA PreCheck, you also have a known traveler number. These programs include TSA PreCheck benefits as part of their enrollment, so you can use the same KTN process when booking domestic flights.
Your Global Entry or NEXUS card will have a KTN printed on it, and you'll find the same number in your enrollment confirmation email and in your account on the program's website. The process for adding it to your airline reservation is identical to TSA PreCheck.
If you're unsure which program you're enrolled in, check your card or log into your account. The program name will be clearly labeled, and your KTN works the same way regardless of which trusted traveler program you hold.
Frequently Asked Questions
Can I use someone else's KTN on my reservation?
No. Your KTN is tied to your identity and TSA record. Using someone else's number won't work—TSA's system will flag the mismatch between the name on your boarding pass and the name associated with that KTN. Always use your own number.
What if my KTN doesn't show up on my boarding pass?
First, check that you entered it correctly—it's nine characters with no spaces or dashes. If it's correct, contact your airline's customer service to confirm the number was saved to your reservation. You can also call TSA PreCheck customer service to verify your KTN is active in their system.
Do I need a new KTN if I renew my TSA PreCheck?
Usually not. Your KTN typically stays the same when you renew. However, if your enrollment was cancelled and you re-enrolled from scratch, you may receive a new number. Check your renewal confirmation email to see which number TSA assigned.
Is my KTN the same as my TSA PreCheck membership number?
No. Your membership number is a longer identifier used for account management and renewal purposes. Your KTN is the shorter nine-character code you use for flight bookings. Both appear in your enrollment documents, but they serve different purposes.