How to Add TSA PreCheck to Your Southwest Flight Booking

Add TSA PreCheck to an existing Southwest reservation through your account

You can add your TSA PreCheck number to a Southwest flight you've already booked by logging into your Southwest account online or through the mobile app. 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, then save the changes. This takes about two minutes and applies to that specific reservation.

If you're booking a new Southwest flight, you can enter your TSA PreCheck number during the checkout process. On the passenger information page, you'll see a section for "Known Traveler Number." Type in your nine-digit number before you complete the purchase. Southwest will then link your PreCheck status to that reservation automatically.

Your TSA PreCheck number is the nine-digit identifier that appears on your approval notice or in your TSA PreCheck account online. It is not your driver's license number or passport number. If you've lost your number, you can find it by logging into your TSA PreCheck account at tsa.gov or by checking any boarding pass from a flight you took after your PreCheck was approved.

Key Takeaways

Add your nine-digit TSA PreCheck number to Southwest reservations through "Manage Reservations" in your account or during checkout when booking a new flight.
You must have an active TSA PreCheck membership before adding the number to any flight—Southwest cannot process the number if your PreCheck has expired or is not yet approved.
Adding your number to your reservation does not may provide PreCheck screening; TSA makes the final decision at the airport based on your background and current status.
If you book through a travel agent or third-party site, you may need to add your TSA PreCheck number directly to your Southwest account rather than during the booking process.

Verify your TSA PreCheck is active before adding it to Southwest

Before you enter your number into any Southwest reservation, confirm that your TSA PreCheck membership is currently active. You can check this by visiting your TSA PreCheck account at tsa.gov, logging in with your credentials, and looking at your membership status and expiration date. If your PreCheck has expired, TSA will not honor the number when you arrive at the airport, and Southwest will not refund your ticket or offer compensation.

If your PreCheck is expired or you have not yet received approval, you will need to renew or complete your initial process before adding the number to a flight. The TSA PreCheck process process typically takes four to six weeks from submission to approval, though this varies. Do not add a number to your Southwest reservation if you are still waiting for approval—wait until you receive your official approval notice with your nine-digit number.

What happens when you add TSA PreCheck to your Southwest booking

When you successfully add your TSA PreCheck number to a Southwest reservation, Southwest sends that information to TSA before your flight. At the airport, TSA uses this information to identify you as a PreCheck member and route you to a dedicated PreCheck screening lane, where the process is typically faster and less invasive than standard screening.

Adding your number does not may provide you will receive PreCheck screening on every flight. TSA makes screening decisions based on your background, travel history, and current threat assessment. Even with a valid PreCheck number on your reservation, TSA may direct you to standard screening if they choose to do so. This is normal and does not indicate a problem with your account or reservation.

If you do not add your TSA PreCheck number to your Southwest reservation, you will go through standard security screening even if you have an active PreCheck membership. Southwest does not automatically link your PreCheck status to your reservation—you must enter the number yourself.

Add TSA PreCheck through the Southwest mobile app

Open the Southwest app and tap "Manage Reservations" at the bottom of the screen. Enter your confirmation number and the last name on the reservation, then tap "Retrieve Reservation." Once your booking appears, look for the passenger information section and tap on the passenger name. Scroll down until you see "Known Traveler Number" and enter your nine-digit TSA PreCheck number. Tap "Save" or "Done" to confirm the change.

The mobile app process is identical to the website version and takes the same amount of time. Changes made through the app sync when ready to your Southwest account online, so you do not need to make the change twice. If you have multiple passengers on your reservation, you will need to add each person's TSA PreCheck number individually.

Correct a mistake or update your TSA PreCheck number on Southwest

If you entered your TSA PreCheck number incorrectly or need to update it because you renewed your PreCheck and received a new number, log back into your Southwest account and follow the same steps you used to add it initially. Go to "Manage Reservations," find your booking, and edit the "Known Traveler Number" field. Delete the old number and enter the correct one, then save the changes.

You can make this correction at any time before your flight. If you discover the error at the airport, speak to a Southwest agent at the ticket counter or gate before you go through security. They can sometimes update your reservation in the system, though TSA may not receive the updated information in time for your flight. It is safer to correct the number online well before you arrive at the airport.

What to do if your TSA PreCheck number won't save in Southwest

If Southwest rejects your TSA PreCheck number or will not let you save it, the most common reason is that you entered the number incorrectly. Double-check that you typed all nine digits with no spaces or dashes. TSA PreCheck numbers contain only numbers—no letters. If you are unsure of your number, log into your TSA PreCheck account at tsa.gov to confirm it before trying again.

Another reason the number may not save is that your TSA PreCheck membership has expired. Check your expiration date on the TSA website. If your PreCheck is expired, you will need to renew it through TSA before Southwest will accept the number. Renewal typically takes four to six weeks.

If you have confirmed your number is correct and your PreCheck is active but Southwest still will not accept it, contact Southwest customer service by phone or through the website. Provide them with your confirmation number and your TSA PreCheck number, and they can manually add it to your reservation. This usually resolves the issue within one business day.

Frequently Asked Questions

Can I add TSA PreCheck to a Southwest flight booked by someone else?

No. Only the person whose name is on the reservation can add their own TSA PreCheck number. If someone else booked the flight for you, ask them to log into their Southwest account and add your number to your passenger record, or contact Southwest customer service with your confirmation number and they can add it for you.

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

Yes. Your TSA PreCheck membership is separate from your Southwest account. You must add your number to each individual reservation you make. Southwest does not automatically link your PreCheck to all your bookings. However, once you add it to a reservation, it stays on that booking even if you modify other details like seat selection.

What if I don't have my TSA PreCheck number yet?

You cannot add a number to your Southwest reservation until you have completed your TSA PreCheck process and received approval. Book your flight now and add the number later once your approval arrives. You can update your reservation at any time before your flight without paying a change fee.

Will adding TSA PreCheck to Southwest cost me extra money?

No. Adding your TSA PreCheck number to a Southwest reservation is free. The cost of TSA PreCheck membership itself is separate and paid directly to TSA, not to Southwest. Southwest does not charge a fee for linking your PreCheck status to your flight.

What if my TSA PreCheck expires before my Southwest flight?

If your PreCheck expires before your flight date, you will not receive PreCheck screening at the airport, even though your number is on your reservation. You will go through standard security screening. Renew your TSA PreCheck before your flight if you want to use it. Renewal applications typically take four to six weeks to process.

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.