Adding/Changing FF#?
 

Is there an easy way to add/change a frequent flyer number on a booked reservation? The website doesn't seem to offer a lot of options when one goes to "manage reservation."

You can add a FF number at online check or at airport

Changing the FF number requires a call to reservations or in person at airport check in desk

I called Aer Lingus and had them add our United Mileage Plus numbers for our family of 4
When I logged back into my Aer Lingus account, I could see the the United numbers on our reservation.

They will also do it via WhatsApp.

Posting an update after our trip.
I realized that when we called the Aer Lingus agent to put our United Frequent flier numbers on our reservations that the agent didn't put the correct numbers with the right person. We are a family of 4 with 2 of the same/similar names/initials so they might have gotten it mixed up. Sigh. Now I need to fix it and we are done with our trip. I tried to fix it online when we were checking in but it kept reverting back to the wrong numbers.

It's also possible to change the number yourself during online check-in.

I did this myself for my last Aer Lingus flight; I flew the outbound using my AerClub number and switched to my BAEC number when checking in for the inbound.

(Still waiting to have the Avios/TPs post in my BAEC account, but that's another story for another day)

I changed my frequent flyer (AerClub number removed, BAEC number added) number on 2 EI bookings by using this online form:
https://www.aerlingus.com/support/cu...ravel-enquiry/
In the Select help request dropdown, I selected "AerClub/Frequent Flyer"

Got a quick response and resolution!