How to Add Your Known Traveler Number to an American Airlines Reservation

Where to enter your Known Traveler Number on American Airlines

You can add your Known Traveler Number (KTN) to an American Airlines reservation in three ways: during booking, after you've booked but before you check in, or at check-in itself. The easiest time is during the initial booking, when the system prompts you for it. If you already have a reservation without a KTN, you can log into your American Airlines account, find the booking, and edit the passenger details to add it there.

American Airlines will ask for your KTN in a field labeled "Known Traveler Number," "KTN," or sometimes "TSA PreCheck/CLEAR/Nexus Number" — they're asking for the same thing. The number itself is nine digits long and comes from TSA PreCheck, CLEAR, Global Entry, NEXUS, or SENTRI, depending on which trusted traveler program you enrolled in.

If you miss adding it before check-in, you can still add it at the airport ticket counter or at a kiosk, though this is less reliable and may not process in time for your flight. The safest approach is to add it to your reservation at least 24 hours before departure.

Key Takeaways

Add your Known Traveler Number during booking by entering it in the TSA PreCheck or trusted traveler field, or edit your reservation afterward in your American Airlines account.
Your KTN is a nine-digit number issued by TSA PreCheck, CLEAR, Global Entry, NEXUS, or SENTRI — you need to have enrolled in one of these programs first.
Adding your KTN to your reservation tells the TSA which security line you're may be able to access for and helps the airline match you to the correct screening.
Add your number at least 24 hours before your flight; adding it at the airport is possible but less reliable.
The same KTN works on all your American Airlines flights and reservations once you add it to your frequent flyer profile.

Adding your KTN during the booking process

When you book a flight on americanairlines.com or through the American Airlines app, the booking form includes a section for trusted traveler information. After you enter your passenger name and date of birth, look for a field that says "Known Traveler Number," "TSA PreCheck Number," or "Trusted Traveler Program." Enter your nine-digit KTN exactly as it appears on your trusted traveler card or enrollment confirmation.

If you're booking through a travel agent or third-party website, that site may not have a field for KTN. In that case, book the flight first, then log into your American Airlines account and add the number to your reservation before check-in. American Airlines will sync the information across their system once you add it.

Double-check that you've entered the number correctly — a typo will prevent the TSA from matching you to your trusted traveler status at security. If you're unsure of your exact KTN, check your trusted traveler program's website or your enrollment confirmation email before you book.

Adding your KTN to an existing reservation

To add your KTN after you've already booked, go to americanairlines.com and select "Manage My Booking." Enter your confirmation number and last name, then click into the reservation. Look for "Passenger Details" or "Edit Passenger Information" and find the field for Known Traveler Number or TSA PreCheck. Enter your nine-digit number and save the changes.

You can also call American Airlines at 800-433-7300 and ask a representative to add your KTN to your reservation. Have your confirmation number and KTN ready when you call. This method is slower but useful if you're having trouble navigating the website or if you're not sure whether your number was entered correctly on a previous booking.

Once you've added your KTN, American Airlines will display it on your boarding pass and send it to the TSA. This update usually takes effect within a few hours, so add it as soon as you realize you forgot — ideally more than 24 hours before your flight.

Adding your KTN to your American Airlines frequent flyer profile

If you're a frequent American Airlines flyer, you can store your KTN in your AAdvantage frequent flyer account so it automatically appears on every reservation you make. Log into your AAdvantage account on americanairlines.com, go to "Profile" or "Account Settings," and look for "Trusted Traveler Information" or "Known Traveler Number." Enter your nine-digit KTN and save it.

Once you've saved your KTN to your profile, it will populate automatically whenever you book a flight under that AAdvantage number. This saves you from having to enter it each time and reduces the chance of typos. If you renew your trusted traveler membership or switch to a different program, update your profile with the new number.

Keep in mind that your KTN in your profile only applies to flights booked under that specific AAdvantage account. If you book a flight without logging in or under a different name, you'll need to add the KTN manually to that reservation.

What happens after you add your KTN

Once your KTN is in the system, American Airlines prints it on your boarding pass. When you arrive at the airport and go through security, the TSA agent scans your boarding pass and sees your KTN. This tells them you're enrolled in a trusted traveler program and may be able to access for expedited screening — either TSA PreCheck (shorter lines, shoes and belt stay on) or CLEAR (skip the line entirely, depending on your program).

The KTN doesn't may provide you'll get PreCheck screening on every flight — the TSA randomly selects some passengers for standard screening even with a valid KTN. But it significantly increases your chances. The number also helps the airline and TSA match you correctly to your reservation, which is especially important if you have a common name.

Your KTN stays valid as long as your trusted traveler membership is active. If your membership expires, you'll need to renew it with the appropriate program (TSA PreCheck, CLEAR, Global Entry, etc.) and update your KTN in your American Airlines account.

Common mistakes when entering your KTN

The most common error is transposing digits or including spaces or dashes. Your KTN is nine digits with no spaces, dashes, or letters — enter it exactly as it appears on your enrollment confirmation or trusted traveler card. If you copy and paste it from an email, make sure you're not accidentally including extra characters.

Another mistake is entering the wrong program's number. If you have both TSA PreCheck and Global Entry, use the number from whichever program you want to use for that flight. They're different numbers, and using the wrong one won't work. Check your enrollment confirmation to confirm which number belongs to which program.

Some travelers add their KTN to their reservation but forget to add it to their frequent flyer profile, so they have to re-enter it on every booking. If you fly American Airlines regularly, take the extra minute to add it to your AAdvantage profile so it's there automatically.

What to do if your KTN doesn't appear on your boarding pass

If you added your KTN but it doesn't show up on your boarding pass, first check that you entered it correctly in your reservation. Log back into your American Airlines account and verify the number matches your trusted traveler card exactly. If it's correct but still not showing, try checking in online 24 hours before your flight — sometimes the system needs time to sync.

If your boarding pass still doesn't show your KTN after online check-in, go to the ticket counter or kiosk at the airport and ask an agent to add it manually. Bring your trusted traveler card or enrollment confirmation so they can verify the number. They can usually update it in a few minutes, and it will print on your new boarding pass.

If you don't have your KTN memorized and can't find your enrollment confirmation, the TSA PreCheck, CLEAR, or Global Entry website can look it up for you if you log into your account. Have this information ready before you go to the airport so there's no delay at check-in.

Frequently Asked Questions

Do I need a Known Traveler Number to fly American Airlines?

No. A KTN is optional and only benefits you if you're enrolled in TSA PreCheck, CLEAR, Global Entry, NEXUS, or SENTRI. Without one of these programs, you don't have a KTN to add. If you fly frequently and want faster security screening, you can enroll in one of these programs and then add your number to your reservations.

What's the difference between TSA PreCheck, CLEAR, and Global Entry?

TSA PreCheck ($78–$85 for five years) gives you expedited security screening at U.S. airports. Global Entry ($100 for five years) includes TSA PreCheck plus expedited customs screening when you return to the U.S. CLEAR ($189 per year) lets you skip the security line entirely by using biometrics. Each has its own nine-digit number, and you add whichever one you're enrolled in to your American Airlines reservation.

Can I use the same KTN on other airlines?

Yes. Your KTN works on every airline — it's issued by the TSA or the trusted traveler program, not by American Airlines. Add it to your reservations with United, Delta, Southwest, or any other carrier the same way you add it to American Airlines.

What if I have multiple trusted traveler programs?

Each program gives you a different nine-digit number. You can only add one KTN per reservation, so choose the program that gives you the benefit you want most for that flight. If you have both TSA PreCheck and CLEAR, for example, add your CLEAR number if you want to skip the line, or your TSA PreCheck number if you just want expedited screening.

Will adding my KTN change my seat or boarding group?

No. Your KTN only affects which security line you use at the airport — it doesn't change your seat, boarding group, or any other part of your reservation. It's purely for TSA screening purposes.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.