How to Link Your TSA PreCheck Number to Frontier

You add TSA PreCheck to your Frontier account by entering your Known Traveler Number (KTN) in your passenger profile before you book or check in for a flight. Frontier does not issue TSA PreCheck itself — you get that through the TSA's official program — but the airline needs your KTN to display the PreCheck indicator on your boarding pass at the airport.

The process takes about two minutes and can be done on Frontier's website or through their mobile app. You will need your KTN, which is a nine-character code the TSA gives you when you complete the PreCheck process and background check. If you have not yet enrolled in TSA PreCheck, you will need to do that first through the TSA's official enrollment centers before you can add it to any airline account.

Key Takeaways

  • Your TSA PreCheck number (KTN) must come from the official TSA PreCheck program, not from Frontier or any airline.
  • You enter your KTN in your Frontier account under "Manage Reservations" or in your profile settings, not during checkout.
  • The KTN appears on your boarding pass only if you add it before you check in for your flight.
  • Adding your KTN to Frontier does not cost anything and does not change your ticket price.

Getting Your TSA PreCheck Number First

Before you can add TSA PreCheck to Frontier, you must complete the TSA PreCheck process through an official enrollment center. The TSA runs these centers at airports, some police departments, and select retail locations like UPS stores. You will pay a fee (currently $78 to $85 depending on the location) and provide your passport or state ID, proof of citizenship or lawful permanent residency, and your Social Security number.

The background check takes about two weeks. Once approved, the TSA mails you a card with your Known Traveler Number printed on it. You can also find your KTN in your TSA PreCheck account online at tsa.gov. Write down or screenshot this nine-character code — you will need it to add PreCheck to Frontier and any other airline you fly.

Adding Your KTN to Your Frontier Account Online

Log into your Frontier account at frontier.com using your email and password. Click on "My Account" or "Manage My Booking" in the top menu, then look for a section labeled "Passenger Information," "Frequent Flyer," or "Known Traveler Number." The exact wording varies depending on when Frontier last updated their website.

Paste or type your nine-character KTN into the field provided. Make sure you enter it exactly as it appears on your TSA card or in your TSA PreCheck account — even one wrong letter will prevent PreCheck from showing on your boarding pass. Save your changes. Frontier will confirm that the number was accepted.

You only need to do this once. After you add your KTN to your Frontier account, it will appear on every boarding pass you print or receive by email, as long as you check in at least 24 hours before departure. If you do not see the PreCheck indicator on your boarding pass, double-check that you entered the number correctly in your account.

Adding Your KTN Through the Frontier Mobile App

Open the Frontier app and tap the menu icon (three horizontal lines) in the bottom right corner. Select "My Account" or "Profile Settings." Scroll down to find "Known Traveler Number" or "TSA PreCheck." Tap the field and enter your nine-character KTN exactly as it appears on your TSA card.

Tap "Save" or "Confirm." The app will verify that the number was entered correctly. Your KTN will now be stored in your Frontier profile and will show on all future boarding passes. The mobile app method works the same way as the website — you only need to enter it once.

What Happens When Your KTN Is on Your Boarding Pass

When your boarding pass displays your TSA PreCheck indicator (usually shown as "TSA Pre✓" or similar), you can use the TSA PreCheck security lane at the airport. This lane typically has shorter lines and allows you to keep your shoes, belt, and light jacket on, leave your laptop and liquids in your bag, and move through security faster.

The PreCheck benefit applies only to flights where your boarding pass shows the indicator. If you book a flight and forget to add your KTN to your Frontier account before checking in, your boarding pass will not display PreCheck, and you will go through standard security screening. You cannot add it after you have already checked in.

Common Mistakes That Prevent PreCheck From Showing

The most common error is entering your KTN incorrectly — even a single wrong character will cause the system to reject it. Copy and paste your number directly from your TSA PreCheck account or card rather than typing it by hand. If you see an error message, go back and check each character one at a time.

Another frequent mistake is checking in for your flight before adding your KTN to your account. Once you check in (whether online, at a kiosk, or at the counter), your boarding pass is locked in. Adding your KTN after that point will not update the pass you already have. Always add your KTN to your Frontier profile before you check in, ideally when you book your ticket or at least 24 hours before departure.

Some travelers also confuse their TSA PreCheck number with their Frontier frequent flyer number or their airline confirmation code. Your KTN is the nine-character code from your TSA PreCheck card only. If you are unsure which number is which, log into your TSA PreCheck account at tsa.gov to find your correct KTN.

What to Do If Your KTN Does Not Appear on Your Boarding Pass

First, verify that you entered your KTN correctly in your Frontier account. Log back in and check the exact spelling and numbers. If the number is correct but PreCheck still is not showing, contact Frontier customer service before your flight. They can sometimes manually add it to your boarding pass if there is a system error, though this is not may provide.

If you are already at the airport and your boarding pass does not show PreCheck, tell the TSA officer at security that you have an active TSA PreCheck membership. They can look up your KTN in the TSA system using your ID and may allow you through the PreCheck lane even if your boarding pass does not display it. This is not automatic, but it is worth asking.

Frequently Asked Questions

Do I have to pay Frontier to add my TSA PreCheck number?

No. Adding your KTN to your Frontier account is free. You only pay for TSA PreCheck itself through the official TSA enrollment program, which costs $78 to $85 for five years. Frontier does not charge anything to link your number to your account.

Can I add my TSA PreCheck number after I book my flight?

Yes, you can add it anytime before you check in. However, you must add it before you check in for your flight — online, at a kiosk, or at the counter. Once you check in, your boarding pass is final and will not update to show PreCheck even if you add your KTN to your account afterward.

What if I have TSA PreCheck but Frontier does not show it on my boarding pass?

Check that you entered your KTN correctly in your Frontier account — even one wrong character will prevent it from showing. If the number is correct, contact Frontier customer service. At the airport, you can also show your TSA PreCheck card to the security officer and ask if they can verify your membership in their system.

Do I need to add my TSA PreCheck number to every airline I fly?

Yes. Each airline maintains its own passenger database, so you must add your KTN to every airline's website or app where you want PreCheck to appear on your boarding pass. Adding it to Frontier does not automatically add it to United, Southwest, or any other carrier.

What is the difference between my TSA PreCheck number and my Frontier frequent flyer number?

Your TSA PreCheck number (KTN) is a nine-character code issued by the TSA and is used for security screening at airports. Your Frontier frequent flyer number is a separate code used to track your miles and rewards with Frontier. You need both in your Frontier account, but they serve different purposes and are not interchangeable.