Add your TSA PreCheck number before or after booking

You can add your TSA PreCheck number to your American Airlines boarding pass in two ways: during the booking process when you first purchase your ticket, or afterward through your reservation. The number appears on your Known Traveler Number (KTN) documentation that TSA sent you when your PreCheck process was approved. American Airlines will then display your TSA PreCheck status on your boarding pass and in the airport system, which tells TSA officers at security that you've been vetted.

The timing doesn't matter much — you can add it months before your flight or the day before departure. However, adding it during booking is simpler because you won't have to search for your reservation later. Either way, the information syncs to your boarding pass within minutes.

Key Takeaways

  • Your TSA PreCheck number is the Known Traveler Number (KTN) printed on the approval letter TSA mailed you after your process was processed.
  • During booking on aa.com, enter your KTN in the "Known Traveler Number" field before you complete your purchase.
  • After booking, log into your American Airlines account, find the reservation, and add your KTN in the passenger details section.
  • Your TSA PreCheck status appears on your boarding pass and in the airport system once the information is saved, usually within minutes.
  • If you don't see TSA PreCheck on your boarding pass after adding your number, contact American Airlines customer service to verify the entry was saved correctly.

Add your KTN during the booking process

When you book a flight on aa.com or through the American Airlines app, you'll see a field labeled "Known Traveler Number" on the passenger information page. This appears after you enter your name, date of birth, and gender. Paste or type your KTN exactly as it appears on your TSA approval letter — it's usually nine characters long and may include letters and numbers.

Leave the field blank if you don't have your KTN handy, and you can add it later. But if you have it available, filling it in now means you won't have to dig through your reservation later. Once you complete your booking, the system stores your KTN with that reservation.

Add your KTN to an existing reservation

Log into your American Airlines account on aa.com and select "Manage Reservations" from the main menu. Enter your confirmation number and last name, then click "Find Reservation." Once your booking appears, click "Passenger Details" or "Edit Passenger Information."

Look for the field labeled "Known Traveler Number" and enter your KTN. Save your changes. American Airlines will update your reservation and send the information to the TSA system. Your boarding pass will reflect your TSA PreCheck status the next time you view it or print it — usually within a few minutes, though it can take up to an hour during busy periods.

Where to find your TSA PreCheck number

Your KTN is printed on the approval letter TSA mailed to you after your PreCheck process was processed. It's a nine-character code that looks something like "ABC123DEF." The letter also includes your PreCheck Known Traveler Number in the header or body text. If you can't find the physical letter, log into your TSA PreCheck account at tsa.gov/precheck to view your approval details and KTN.

Do not confuse your KTN with your TSA PreCheck membership number or your confirmation number from the TSA process. The KTN is the specific code you enter into airline systems. If you're unsure which number to use, the TSA website shows your KTN clearly labeled in your account dashboard.

Verify your TSA PreCheck appears on your boarding pass

After you add your KTN and save your reservation, pull up your boarding pass on aa.com, in the American Airlines app, or at the airport kiosk. Look for text that says "TSA PreCheck" or "TSA PRE✓" printed on the pass. This confirms the airline received your KTN and sent it to the TSA system.

If you don't see TSA PreCheck on your boarding pass after waiting an hour, double-check that you entered your KTN correctly — no extra spaces, no typos. Then contact American Airlines customer service by phone or through the app to confirm the number was saved to your reservation. They can verify the entry in their system and resubmit it if needed.

What happens at security with TSA PreCheck on your pass

When you arrive at the security checkpoint, the TSA officer scans your boarding pass and sees your PreCheck status in their system. This tells them you've already been vetted through the TSA PreCheck program. You'll be directed to a dedicated PreCheck lane, where you can leave your shoes, belt, and light jacket on, keep your laptop and liquids in your bag, and move through screening faster than standard passengers.

Having your KTN on your boarding pass is what triggers this — without it, you won't be routed to the PreCheck lane even though you have an active PreCheck membership. That's why adding your number before each flight matters, even if you've flown many times before.

Common mistakes when adding your KTN

The most frequent error is entering the wrong number. Passengers sometimes use their TSA PreCheck membership number (a longer code) instead of their Known Traveler Number (the nine-character KTN). Check your approval letter again and make sure you're copying the field labeled "Known Traveler Number" or "KTN," not any other identifier.

Another mistake is adding spaces or dashes that weren't in the original number. Copy and paste your KTN directly from your TSA account or approval letter if possible, rather than typing it by hand. If you've already entered it incorrectly, go back into your reservation, clear the field, and re-enter it correctly. American Airlines will update the system once you save the change.

Frequently Asked Questions

Do I have to add my KTN to every flight I book?

Yes. Each reservation is separate, so you need to add your KTN to each ticket you purchase. It takes less than a minute during booking, or you can add it afterward through your reservation. Some airlines link your KTN to your frequent flyer account so it auto-fills, but American Airlines does not do this — you must enter it manually for each booking.

What if I don't have my KTN when I book?

You can leave the field blank and add it later through your reservation. Log in, find your booking, edit passenger details, and enter your KTN. Do this at least a few hours before your flight so the system has time to sync with TSA. Adding it the day before is safest.

Can I use someone else's KTN on my boarding pass?

No. Your KTN must match your name and date of birth on your ticket. TSA officers verify this at the checkpoint. Using someone else's number will cause a mismatch in the system and you won't be cleared for the PreCheck lane.

Will I lose TSA PreCheck if I don't add my KTN to my boarding pass?

Your TSA PreCheck membership stays active regardless. However, without your KTN on your boarding pass, TSA won't know you have PreCheck when you arrive at security, and you'll go through standard screening. Your membership is still valid — you just won't get the PreCheck benefit on that particular flight.

What if my boarding pass still doesn't show TSA PreCheck after I added my KTN?

Wait at least an hour for the system to update, then check your boarding pass again. If it still doesn't appear, contact American Airlines customer service with your confirmation number. They can verify the KTN was entered correctly and resubmit it to TSA if there was a system error. Bring your TSA PreCheck approval letter to the airport as backup.