How to Add TSA PreCheck to Your Southwest Flight Reservation

Add TSA PreCheck to an existing Southwest booking through your account

If you already have a TSA PreCheck membership and a Southwest flight booked, you can link them together in your Southwest account. Log into Southwest.com, go to "Manage Reservations," find your booking, and look for a field labeled "Known Traveler Number" or "KTN." Enter your nine-digit TSA PreCheck number there. Southwest will then display your TSA PreCheck status on your boarding pass when you check in.

The TSA PreCheck number appears on your membership card or in your TSA PreCheck account at tsa.gov. If you cannot find it, log into your TSA PreCheck account under "Manage process" and look for the "Known Traveler Number" section. Once you add it to Southwest, the change takes effect when ready—you do not need to reprint your boarding pass or contact Southwest directly.

You can also add your TSA PreCheck number when you first book a Southwest flight. During the booking process, Southwest asks for your Known Traveler Number before you complete payment. Entering it at that point saves a step later.

Key Takeaways

Your TSA PreCheck number is a nine-digit code that appears on your membership card and in your TSA PreCheck account at tsa.gov.
Add your number to Southwest through "Manage Reservations" on Southwest.com by entering it in the Known Traveler Number field.
You can add your TSA PreCheck number when you first book a flight or update an existing reservation at any time before you fly.
Once linked, your TSA PreCheck status will print on your boarding pass, and you can use expedited security lanes at the airport.

What happens after you add your TSA PreCheck number

After you enter your TSA PreCheck number into Southwest, your boarding pass will show "TSA Pre✓" next to your name when you check in online, at a kiosk, or at the gate. This tells TSA agents at security that you are a PreCheck member and may be able to access for expedited screening.

Expedited screening means you can keep your shoes, belt, and light jacket on, leave your laptop and liquids bag in your carry-on, and go through a dedicated TSA PreCheck lane at most major airports. The process is faster than standard screening, though wait times vary by airport and time of day.

Your TSA PreCheck status applies to all flights you take, not just Southwest. If you book flights on other airlines, add your TSA PreCheck number to those reservations the same way—each airline has a Known Traveler Number field in its booking system.

If you do not have TSA PreCheck yet

TSA PreCheck is a separate membership program that costs $78 to $85 for five years, depending on your location and whether you renew or explore new. You must explore through the TSA at tsa.gov/precheck, not through Southwest. The process includes a background check and an in-person appointment at an enrollment center to verify your identity and take your fingerprints.

The entire process typically takes four to six weeks from process to approval. Once you are approved, you receive a membership card by mail with your nine-digit Known Traveler Number printed on it. You can then add that number to any airline reservation, including Southwest.

If you want TSA PreCheck benefits for an upcoming Southwest flight but have not yet applied, you will not have time to complete the full process before your trip. In that case, you can only use standard security screening for that flight.

Updating your TSA PreCheck number if it changes

Your TSA PreCheck number stays the same for the entire five-year membership period. However, if you renew your membership after it expires, you may receive a new number. When that happens, you need to update the number in all your airline reservations.

Log back into Southwest.com, go to "Manage Reservations," and replace the old number with your new one. Do this before your flight so that your boarding pass prints with the correct number. If you forget and your old number appears on your boarding pass, you can still use TSA PreCheck screening if you bring your current membership card to the security checkpoint—TSA agents can verify your status manually.

Troubleshooting: Your TSA PreCheck is not showing on your boarding pass

If you added your TSA PreCheck number to Southwest but it does not appear on your boarding pass, check that you entered the number correctly. The Known Traveler Number is always nine digits. Log back into your reservation and verify the number matches what is printed on your TSA PreCheck card or listed in your TSA account at tsa.gov.

If the number is correct but still does not show, try checking in again online or at a Southwest kiosk. Sometimes the system needs a few hours to sync after you make changes. If you are at the airport and your boarding pass still does not show TSA PreCheck, bring your membership card to the security checkpoint and show it to the TSA agent—they can verify your status and let you use the expedited lane.

In rare cases, there may be a delay between when TSA approves your membership and when the number becomes active in airline systems. If you just received your membership card, wait 24 hours before adding it to Southwest, then try again.

Adding TSA PreCheck to Southwest flights booked by someone else

If someone else booked your Southwest flight—a travel agent, a family member, or your employer—you can still add your TSA PreCheck number. You need the confirmation number for the reservation. Go to Southwest.com, click "Manage Reservations," enter the confirmation number and your name, and then add your Known Traveler Number to that booking.

You do not need permission from the person who booked the flight. Your TSA PreCheck number is tied to your identity, and you can update it on any reservation that includes your name as a passenger.

Frequently Asked Questions

Can I add TSA PreCheck to a Southwest flight after I check in?

You can add your TSA PreCheck number to your reservation at any time, but it works best if you do it before you check in. If you add it after checking in, your boarding pass may not update to show TSA PreCheck status. At the airport, bring your membership card to the security checkpoint and show it to the TSA agent—they can verify your status manually and let you use the expedited lane.

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

Yes, you need to add your number to each individual reservation. Southwest does not automatically link your TSA PreCheck membership across all your bookings. However, once you add it to a reservation, it stays linked to that specific flight even if you change other details like your seat.

What if my TSA PreCheck membership expired?

If your membership has expired, your Known Traveler Number is no longer active, and TSA will not honor it at security. You must renew your membership through tsa.gov before adding the number to a flight reservation. Once renewed, you will receive a new card with a new number, which you can then add to Southwest.

Does Southwest charge extra to add TSA PreCheck to my reservation?

No. Southwest does not charge a fee to link your TSA PreCheck number to your reservation. The only cost is the TSA PreCheck membership itself, which you pay directly to TSA when you explore or renew.

Can I use TSA PreCheck on Southwest flights to international destinations?

TSA PreCheck applies only to domestic flights departing from U.S. airports. If you are flying Southwest to Mexico, Canada, or another country, you can use TSA PreCheck for the U.S. security screening before your flight, but the program does not cover screening in other countries.

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.