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Frequent flyer number, passport number and trip confirmation number are a few pieces of information you might like to keep handy when travelling.

If you have a known traveler number, you can use it if you have global entry. Access to the PreCheck lanes is ensured by this number.

What to know about getting a KTN, how to find it, and how to make sure it is attached to your flight reservations are included in this article.

What is a Known Traveler Number?

Upon approval for one of the two programs, a nine-digit code is sent to the member. A few of the Trusted Traveler Programs give their members a KTN.

There is a chance that the code is a combination of both letters and numbers.

If you have an identification number that shows you are a member of one of these programs, you can use the PreCheck lanes at U.S. airports.

Travelers who go through an application and screening process are known as travelers by the US government.

Passengers proceed through the TSA security checkpoint at Denver International Airport in August 2019. ROBERT ALEXANDER/GETTY IMAGES

Should you apply for a Known Traveler Number?

It's your key to access the PreCheck lanes because they have shorter wait times and are less intrusive than the standard lanes.

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There are a number of ways to get a KTN.

Travelers are required to submit an application in order to participate in the program. Interviews for first-time applicants are usually done in person at an enrollement center. Some people are able to apply for virtual interviews when they want to renew their membership.

The memberships in all the programs are valid for five years. Application fee credits are offered by many credit cards.

TSA PreCheck entrance inside Terminal 1 at Raleigh/Durham International Airport (RDU). SEAN CUDAHY/THE POINTS GUY

TSA PreCheck

If you received confirmation of your approval into the program after applying for the program, you will receive a KTN.

The security experience for the members is fast. You don't have to remove your shoes, take your laptop or liquids out of your bag when you go through the PreCheck lanes.

The fee is applied to

Is it possible to be denied for global entry or pre check? There is a way to appeal.

Global Entry

If you received your PreCheck membership by applying for Global Entry, you'll be able to receive your KTN through your Global Entry membership.

Travelers who are designated by the U.S. government as low risk can use faster customs lines when returning to the U.S. The members also have access to the PreCheck program.

There is a fee for applying to this program.

If you're going to travel internationally and within the U.S. in the next five years, Global Entry is probably your best bet since it gets you expedited screening both at customs and at the airport for less than a standard PreCheck membership.

There are things you should know about global entry.

NEXUS and SENTRI

Travelers from Canada and/or Mexico can enter the U.S. through the Trusted Traveler program. NEXUS and SENTri give members access to the PreCheck program.

Pre-screened travelers can use NEXUS to enter the US from Canada. $50 is the fee for this program.

Pre-screened travelers can enter the U.S. via air, land or sea. There is an application fee for this program.

Global Entry can save you time and energy when you’re flying back into the U.S. from abroad. PAUL J. RICHARDS/AFP/GETTY IMAGES

How do you add a Known Traveler Number to your airline ticket?

You have to attach your number to your airline's profile to make sure your number is printed on your boarding pass.

Attaching your number to a single reservation can be done when you fill out your personal information at the checkout.

Frequent flyer accounts can be used to earn miles. The personal information section of your airline profile can be attached if you have an account.

If you do this, your KTN will be added to every reservation you make with that airline.

It's possible to add your KTN to an existing reservation.

If a boarding pass is not marked, what to do?

Where can you find your Known Traveler Number?

When booking a flight or updating your airline profile are the times when you will most likely need KTN.

This applies to people who have joined one of the programs but haven't flown with an airline yet.

For the first time since becoming a Global Entry member, I was able to book a flight through the website of JetBlue. I updated my TrueBlue profile to make sure my boarding pass says "TSA Precheck" when I check in, because of that.

JETBLUE.COM

With all the numbers, passwords and accounts we have to keep track of in our lives, it's easy to lose your KTN... and most of us probably don't know your number by heart

You can use this page from the DHS to put in your personal information if you want to look up your number.

TSA

You have two options if you received your KTN through Global Entry. Check the back of your Global Entry card. Your nine-digit "PASSID" may be "15," "98," or "99."

I have circled the location of my number on my card and blurred out the digits.

The location of a Known Traveler Number on a Global Entry card is circled in blue. SEAN CUDAHY/THE POINTS GUY

If you log in to your Global Entry or other Trusted Traveler Program account, you should be able to see which program you're Enrolling in, as well as your PASSID, which is your KTN. When your membership ends, you should be able to see it.

DEPARTMENT OF HOMELAND SECURITY

There are at least three ways you can find your number. Think about which airline you've flown with if your membership in one of the Trusted Traveler programs is active. It's probably on file with that airline.

If you go to your profile with that airline, you should see it listed. I pulled up my personal information on the American Airlines app to locate my KTN. Under "secure traveler" it is listed.

AA.COM

Bottom line

There is a code that will get you into the Pre Check lane. It is the way the airline and government recognize a traveler who is a member of a program.

Add your number to your profile. If you aren't a member, you can enroll in one of the programs that will give you a KTN and make your trip through the airport less of a hassle.