To recover your Known Traveler Number, there are two possibilities:If you got a KTN through TSA PreCheck enrollment (paid $85), you should call the Universal Enrollment Service at
855 - 347 - 8371.
If you got a Known Traveler Number through one of the other Trusted Traveler Programs (paid $100), you can look on the back of your Membership ID card where you see "PASS ID." The number should be there. If you do not have your membership ID card for some reason, you can call the Customs and Border Protection, which runs the other Trusted Traveler programs, to find your KTN: 855 - 873 - 4637.
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