Can I get the airline booking reference and ticket number through the API as soon as a booking is made so I can send them to my customer?

Yes, in most cases you can get both straight from the API, and you do not need to log into the airline site to find them.

When a booking goes through, the reply from the API normally includes the airline booking reference, the short code your customer sees on their itinerary. The ticket number is slightly different, because it only exists once the ticket has actually been issued. With many low cost carriers, booking and ticketing happen in the same step, so the reference and the ticket number come back together. With content that comes through a global distribution system, ticketing is often a separate call, so the reference arrives first and the ticket number a moment later, once issuance is confirmed.

This does depend on the supplier and on how your account is set up. A few suppliers return the reference immediately but hold the ticket number until their own issuance finishes, and now and then a booking sits in a manual queue on their side and takes longer. In those cases you read the booking again with the same reference and the number is there. Because of that, it is safer to save the reference against your booking record as soon as you have it, then fill in the ticket number when it arrives, rather than waiting for both before you store anything.

Once you are connected, make a test booking in the sandbox and look at exactly which fields come back in the booking response, then ask your supplier whether ticket numbers are returned in that same response or need a separate retrieve call, so your confirmation emails never go out with a blank ticket number.