You add TSA PreCheck or REAL ID information when you book your flight, not after

The TSA PreCheck number and REAL ID status do not get added to a boarding pass you already have. Instead, you provide this information during the booking process — either when you first purchase your ticket or by editing your reservation before you check in. The airline's website or app will ask for your Known Traveler Number (KTN) if you have TSA PreCheck, and your REAL ID-compliant driver's license or passport details if that is what you are using for identification.

If you have already booked a flight without entering this information, you can go back into your reservation and add it. Most airlines let you do this up to 24 hours before departure through their website or mobile app. The process takes a few minutes and does not require you to rebook or pay a new fare.

Key Takeaways

  • Add your TSA PreCheck Known Traveler Number (KTN) during booking or by editing your reservation before check-in.
  • Your KTN appears on your boarding pass only if the airline's system recognizes it and your TSA PreCheck membership is current.
  • REAL ID status is verified at the airport using your driver's license or passport, not entered into the booking system.
  • If your boarding pass does not show TSA PreCheck, check that your KTN is correct and your membership has not expired.

Where to enter your TSA PreCheck number during booking

When you book a flight on an airline's website or app, look for a field labeled "Known Traveler Number," "KTN," or "Frequent Traveler Information." This field usually appears on the same page where you enter your name and contact details. Enter your nine-digit TSA PreCheck number exactly as it appears on your approval letter or in your TSA account.

If you are booking through a third-party site like Kayak, Expedia, or Google Flights, you may not see this field during the initial booking. In that case, you will need to go to the airline's website directly and add your KTN by editing your reservation. Use your confirmation number and last name to pull up your booking, then look for a "Manage Reservation" or "Edit Booking" option.

How to add TSA PreCheck to an existing reservation

Log into the airline's website or open their mobile app and find the option to manage or view your reservation. You will typically need your confirmation number and the last name on the booking. Once you pull up your flight, look for an "Edit" or "Manage" button.

From there, select the option to add or update frequent traveler information. Enter your TSA PreCheck Known Traveler Number in the field provided. Save your changes. The airline's system will then pass this information to TSA, and your boarding pass should reflect your PreCheck status when you check in or print it.

You can make this change up to 24 hours before your flight on most airlines. After that window closes, you may not be able to add it online, though you can still ask a gate agent or ticket counter agent to manually add it when you arrive at the airport.

Why your boarding pass might not show TSA PreCheck even after you add your number

The most common reason is that your TSA PreCheck membership has expired. Check the expiration date on your approval letter or log into your TSA account at tsa.gov to confirm your membership is still active. TSA PreCheck is valid for five years from the date of approval.

A second reason is that you entered your KTN incorrectly. Your Known Traveler Number is nine digits long and should match exactly what appears on your TSA approval documents. Even a single digit off will prevent the airline from linking your PreCheck status to your booking.

Third, the airline's system may not have synced with TSA's database yet. This is rare but can happen if you added your KTN very close to your flight time. If your boarding pass does not show PreCheck status, bring your TSA approval letter or your membership card to the airport. The TSA officer at security can verify your PreCheck status manually.

REAL ID and your boarding pass

REAL ID status does not appear on your boarding pass the way TSA PreCheck does. Instead, REAL ID is verified at the airport when you show your driver's license or passport to the TSA officer. Your boarding pass itself does not need to contain any REAL ID information.

What matters is that the ID you present at security is REAL ID-compliant. A REAL ID driver's license or passport has a gold star or other marking in the upper right corner. If you have a REAL ID-compliant ID, you can use it for domestic flights. If you do not, you will need a passport or other federal ID.

What happens at security if your boarding pass does not show PreCheck

If your boarding pass does not display the TSA PreCheck indicator but you have an active membership, tell the TSA officer at the security checkpoint. Bring your TSA approval letter, membership card, or any document showing your Known Traveler Number. The officer can verify your PreCheck status in the system and may allow you to go through the PreCheck lane even without the indicator on your boarding pass.

This happens often enough that TSA officers are used to it. The key is to arrive early and be prepared to show proof of your membership. Do not assume you will be turned away from the PreCheck lane — ask the officer first.

Frequently Asked Questions

What is my Known Traveler Number and where do I find it?

Your Known Traveler Number (KTN) is a nine-digit code assigned to you when you are approved for TSA PreCheck. You can find it on your TSA approval letter, your TSA PreCheck membership card, or by logging into your account at tsa.gov. It is not the same as your confirmation number from your flight booking.

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

No. Once you have checked in, your boarding pass is locked and cannot be changed. You must add your KTN before you check in — either during booking or by editing your reservation up to 24 hours before departure. If you miss this window, you can still show your TSA approval letter at security and ask the officer to verify your status.

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

Yes. Each time you book a new flight, you should add your KTN to that specific reservation. Some airlines offer the option to save your KTN to your frequent flyer profile, which will automatically populate it on future bookings, but this is not may provide on all airlines or all booking methods.

What if I do not have a TSA PreCheck number yet?

You cannot add a KTN to your boarding pass if you do not have TSA PreCheck membership. You can still travel domestically with a REAL ID-compliant driver's license or passport. If you want TSA PreCheck, you will need to go through the process process at tsa.gov, which includes an in-person appointment and a background check.

Will adding my TSA PreCheck number cost me anything?

No. Adding your Known Traveler Number to your boarding pass is free. TSA PreCheck membership itself costs money (currently $78 to $85 for five years), but once you have paid for membership, there is no additional charge to use it on your flights.