Originally Posted by
ROKNA
Now really official
https://www.aerlingus.com/prepare/ai.../tsa-precheck/
Only can you get the KTN added at check in or by contacting customer service. Note when departing from the US you need to go to a check in desk even if checked in online for passport/visa check so not really additional pain. Makes no difference flying to the US
That page seems to contradict itself about whether you can add your KTN during online check in. First it says
To use your TSA PreCheck benefits, add your KTN/PASS ID:
- When checking in at the airport
- Or, by contacting Aer Lingus helpdesk before checking in
Later it says "When checking in online, please ensure you are using a valid KTN." I hope the latter is true and you can add it during online check in. We flew BOS-DUB on EI in May and didn't stop at a check in desk because we weren't checking bags. They checked our passports at the gate. It's not a big deal to have to go to a desk but I like to avoid it when possible.