Hello, and welcome.
If you have TSA Precheck, it is good for all airlines that participate in the program, but it is recommended that you do register with, or add to your profile for, all airlines that you fly/fly frequently, so you can get the advantage there, too. When you make your reservation with whichever airline, if they are a participant, make sure to give them your TSA Precheck KTN (Known Traveler Number,) so it goes on your reservation and boarding pass.
I hope this helped!
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