Put your TSA PreCheck number in the "Known Traveler Number" field when you book your flight or check in online

American Airlines asks for your TSA PreCheck number in a specific place during booking or check-in. The field is labeled Known Traveler Number (KTN), and that is where you enter your nine-digit TSA PreCheck membership number. If you add it before you fly, the TSA PreCheck indicator will show on your boarding pass, which tells TSA officers at security that you have already been vetted.

You can add your number at three different points: when you first book your ticket online, when you manage your reservation later, or during online check-in up to 24 hours before departure. The earlier you add it, the more likely it will print on your boarding pass. If you forget to add it before you arrive at the airport, you can still tell the gate agent or ticket counter staff, though it may not appear on your pass.

Key Takeaways

  • The TSA PreCheck number field on American Airlines is called "Known Traveler Number" and accepts your nine-digit membership number.
  • You can enter your number during online booking, in your reservation management page, or during online check-in up to 24 hours before departure.
  • Adding your number before you check in increases the chance it will print on your boarding pass, which is what TSA officers look for at security.
  • If you do not add it online, you can provide your TSA PreCheck number to the ticket counter or gate agent on the day of travel.

Adding your number during online booking

When you book a flight on americanairlines.com or the American Airlines app, you will see a field for "Known Traveler Number" on the passenger information page. Enter your nine-digit TSA PreCheck number exactly as it appears on your membership card. Do not add spaces or dashes—just the nine digits.

If you are booking for multiple passengers, each person needs their own TSA PreCheck number entered in their own field. Family members traveling together each have separate membership numbers, so add each one individually. Once you complete the booking, the number is saved to that reservation.

Adding your number to an existing reservation

If you already booked your flight without adding your TSA PreCheck number, you can add it later through your reservation. Go to americanairlines.com, click "Manage Reservations," and enter your confirmation number and last name. Once you see your booking details, look for the passenger information section and find the "Known Traveler Number" field.

You can update this information any time before your flight, though American Airlines recommends doing it at least 24 hours before departure to may support it prints on your boarding pass. If you update it closer to your flight time, the number may not appear on your pass, but you can still show your TSA PreCheck card at security.

Adding your number during online check-in

American Airlines allows online check-in starting 24 hours before your flight. During this process, you will see a section for passenger details where you can enter or update your "Known Traveler Number." If you did not add it during booking or reservation management, this is your final note to add it before you arrive at the airport.

Check in online as soon as the 24-hour window opens to give the system time to update your boarding pass. If you check in very close to departure, the number may not process in time to print on your pass, but you can still present your TSA PreCheck card to the security officer.

What happens if your number does not appear on your boarding pass

If your TSA PreCheck number does not print on your boarding pass, you can still use your benefits at security. Bring your physical TSA PreCheck card or your membership letter along with your boarding pass and ID. Show the TSA officer your card, and they will process you through the TSA PreCheck lane even if the indicator is not on your pass.

The boarding pass indicator is a convenience—it alerts the TSA officer before they scan your pass—but it is not required to use your membership. Many travelers forget to add their number online and straightforward show their card at the checkpoint. The process takes a few extra seconds, but you still get through the expedited line.

Entering your number at the airport

If you arrive at the airport without having added your TSA PreCheck number online, you can provide it to the ticket counter agent or gate agent before you go through security. They can note it in the system, though it may not update your boarding pass at that point. Your best option is to show your TSA PreCheck card directly to the TSA officer at the security checkpoint.

The TSA officer will verify your membership using your card and let you proceed through the PreCheck lane. This adds a minute or two to the process compared to having the number on your pass, but you will still benefit from shorter lines and the ability to keep shoes, belt, and light jacket on.

Finding your TSA PreCheck number if you have lost it

Your TSA PreCheck number is printed on your membership card. If you have lost the card, you can find your number by logging into your TSA account at tsa.gov. Go to "Manage Your Membership" and your Known Traveler Number will be displayed there. You can also call the TSA at 1-855-347-8371 to request your number over the phone.

Once you have your number, enter it into your American Airlines reservation using any of the methods described above. Your membership is still active even if your physical card is lost—you just need the nine-digit number to prove it at security.

Frequently Asked Questions

Can I add my TSA PreCheck number after I have already checked in?

No, once you have checked in (online or at the airport), the boarding pass is locked and cannot be updated. If you realize you forgot your number after checking in, show your TSA PreCheck card directly to the security officer. They can verify your membership using the card.

Do I need to add my TSA PreCheck number for every flight?

No. Once you add your number to your American Airlines frequent flyer profile, it will automatically populate on future bookings under that account. You only need to enter it once per reservation if you are booking under a different name or account.

What if I have TSA PreCheck but my family members do not?

Each passenger needs their own TSA PreCheck number to use the benefit. Add your number to your field and leave the other passengers' fields blank. You will go through the PreCheck lane, and they will go through standard security. Children under 12 can go through PreCheck with an adult who has the membership, even without their own number.

Will my TSA PreCheck number work on connecting flights?

Yes, as long as you have added it to your reservation, it will appear on all boarding passes for that trip, including connections. If you are booking separate tickets for each leg, you will need to add your number to each reservation individually.

What if the website will not accept my TSA PreCheck number?

Make sure you are entering exactly nine digits with no spaces, dashes, or letters. Double-check that you have copied the number correctly from your membership card or TSA account. If the system still rejects it, contact American Airlines customer service or the TSA to verify that your membership is active and your number is correct.