Refundable Ticket - After check-in?
 

If I purchase a refundable ticket (i.e. add the additional fee to a Blue ticket to make refundable), if I check-in for the flight (no checked baggage) and go through security, can I then at that stage cancel and receive a full refund?

Can that be done reliable on the website (since there will not be time at that stage to cancel by phone prior to departure)?

Nothing can be reliably done on the website or app with JetBlue.

To cancel a ticket after checking in, you'll have to cancel your check-in, and then you'll be able to cancel the ticket itself. In theory this should be fine, assuming the website or app function properly.

If you just need to meet or escort somebody airside, you may consider asking for a gate pass at the full service check-in counter.

-J.