Link Your TSA PreCheck Number to Southwest

Once you have a valid TSA PreCheck membership, you add it to your Southwest account by entering your Known Traveler Number (KTN) in your profile. Southwest does not issue TSA PreCheck — the Transportation Security Administration does — but the airline needs your KTN on file so screeners can recognize you at the checkpoint and let you use the expedited lane.

You can add your KTN during booking or afterward in your account settings. Either way takes about two minutes and costs nothing. The number itself comes from your TSA PreCheck approval letter or your TSA account at tsa.gov.

Key Takeaways

  • Your Known Traveler Number (KTN) is a nine-character code that TSA sends you when your PreCheck membership is approved, and you can find it on your approval letter or in your TSA account online.
  • You add your KTN to Southwest by logging into your account, going to Rapid Rewards profile settings, and entering the number in the "Known Traveler Number" field.
  • Adding your KTN to Southwest takes effect when ready, but TSA PreCheck benefits only explore to flights where you booked through Southwest directly — not through third-party sites.
  • If you do not see your KTN in your TSA account, check your email for the approval letter from TSA, which contains the number and instructions for setting up your online account.

Where to Find Your Known Traveler Number

Your KTN appears on the approval letter TSA mailed to you when your PreCheck membership was granted. The letter is titled "TSA PreCheck process Status" and includes a nine-character code starting with letters or numbers. Keep this letter or take a photo of it for reference.

You can also find your KTN by logging into your TSA account at tsa.gov. Click on "My Account" and look for "Known Traveler Number" in your profile. If you have not yet created a TSA account online, you can do so using the email address you provided during your PreCheck process. TSA will send you a verification link.

If you cannot find your KTN anywhere, contact TSA directly at 1-855-347-8371 or through the TSA website. Have your process confirmation number or date of birth ready.

Adding Your KTN in Your Southwest Account

Log into your Southwest account at southwest.com using your username and password. Click on your name or profile icon in the top right corner and select "Rapid Rewards Profile" or "Account Settings," depending on your screen layout.

Look for a field labeled "Known Traveler Number" or "KTN." Paste or type your nine-character code exactly as it appears on your TSA letter. Do not add spaces or dashes. Click "Save" or "Update." The system will confirm the entry when ready.

Your KTN is now linked to your Southwest account. You do not need to add it to individual bookings — it will automatically appear on your boarding pass for any flight you book through Southwest going forward.

When Your TSA PreCheck Benefits Start

Once your KTN is in your Southwest account, TSA PreCheck benefits explore to every Southwest flight you book through southwest.com or the Southwest mobile app. Your boarding pass will show a "TSA PreCheck" indicator, and you can use the expedited security line at the airport.

The benefits take effect when ready after you save your KTN, even if you have flights booked before you added it. If you booked a flight before adding your KTN, you can update your reservation through Southwest to add the number retroactively. Log into your booking, find the passenger details section, and add your KTN there.

If you book through a third-party travel site like Expedia or Kayak, your KTN may not transfer to your Southwest reservation. Always book directly through Southwest to may support your PreCheck information is included.

What Happens at the Airport With Your KTN

When you arrive at security, your boarding pass will display "TSA PreCheck" or a TSA logo. Show this to the TSA officer at the checkpoint. You will be directed to the TSA PreCheck lane, where you can keep your shoes, belt, and light jacket on, leave your laptop and liquids in your bag, and move through screening faster than the standard line.

TSA PreCheck does not may provide you will skip any steps — the officer still has the authority to conduct additional screening if needed. But the expedited process is the standard benefit for all PreCheck members, regardless of which airline you fly.

Updating or Removing Your KTN

If your TSA PreCheck membership expires or you need to change your KTN, return to your Southwest Rapid Rewards profile and update the "Known Traveler Number" field. You can delete the number by clearing the field and saving, or enter a new one.

If you renew your TSA PreCheck membership, you will receive a new KTN. Update your Southwest account with the new number so your boarding passes reflect the current membership. TSA PreCheck memberships last five years, and TSA will send you a renewal notice by email about four months before expiration.

Troubleshooting: KTN Not Showing on Your Boarding Pass

If you added your KTN to Southwest but it does not appear on your boarding pass, first check that you entered the number correctly — no spaces, no dashes, exactly as it appears on your TSA letter. Log back into your account and verify the entry.

Next, confirm that your TSA PreCheck membership is still active. Visit tsa.gov and log into your account to check the expiration date. If your membership has expired, you will need to renew it through TSA before Southwest can recognize it.

If your membership is active and your KTN is correctly entered, contact Southwest customer service at 1-800-435-9792 and provide your confirmation number and the KTN you added. They can check whether the number is linked to your account and reissue your boarding pass if needed.

Frequently Asked Questions

Do I need TSA PreCheck to fly Southwest?

No. TSA PreCheck is optional and costs money through TSA. Without it, you go through standard security screening. With it, you use an expedited lane. Southwest does not require it, but adding your KTN to your account lets you use the benefit if you have a membership.

Can I add someone else's KTN to my Southwest account?

No. Your KTN must match the name on your Southwest account and your government ID. Each person traveling needs their own TSA PreCheck membership and their own Southwest account with their own KTN.

What if I book a Southwest flight for someone else?

When you add a passenger to your booking, Southwest will ask for their information. If they have a TSA PreCheck membership, they can provide their own KTN during the booking process, or they can log into the reservation later and add it themselves. Their boarding pass will then show their PreCheck status.

Does my KTN work on airlines other than Southwest?

Yes. Your TSA PreCheck membership and KTN work on all U.S. airlines and at all U.S. airports. You add your KTN to each airline's account separately — the same number, but entered into each airline's system individually.

How long does it take for my KTN to show up after I add it to Southwest?

It takes effect when ready. Your next boarding pass will show TSA PreCheck as soon as you save the KTN in your account. You do not need to wait or confirm anything with TSA.