The ticket number can be found on your:
Confirmation email and receipt – look toward the end of the email under the 'Receipt' section Receipt from Airport / City Ticket Office – look at the bottom in the middle of the ticket Credit card statement
The ticket number is 13 characters long and also contains the airline code. The ticket number is the last 10 digits. Keep in mind there are separate ticket numbers for add-ons like seats, upgrades and bags.