Hello, I am James and I am a new Expert. I will provide you with a thorough response, including informative links to help you. Kindly remember to rate my customer service before leaving the site today. You are the only person who can give me credit for my effort.
Since SWA mentioned TSA PreCheck only, I will stick with that procedure.
TSA PreCheck Participation
To get into the TSA PreCheck program you will need to go to an Enrollment Center. Here is a link to find the nearest enrollment center: https://universalenroll.dhs.gov/locator.
Prior to going, you should pre-apply to make things go faster. The process for Pre-Application can be found here: https://universalenroll.dhs.gov/.
Once you have completed the application and appointment, and you are issued a PreCheck number, you will use that when making your reservations. In the reservation process, there will be a space or option in your booking process that asks for a "Known Traveler Number" or "KTN." This is where you include the PreCheck number. This will make you eligible for PreCheck status and expeidted screening.
Note that expedited service is not always guaranteed. For security reasons, you may not always be chosen for PreCheck, even if you put in your KTN. So you can be offered PreCheck for one trip, but not necessarily another. Only when you see "TSA PreCheck" on the boarding pass will you be able to actually use the expedited screening process at the airport. This randomization is meant to increase security measures. You can find this information here, under "Other Ways to Experience TSA PreCheck": http://www.tsa.gov/tsa-precheck/participation-tsa-precheck%C2%AE.
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