Name on Passport?

Arrow in the Knee

Ok so when booking a flight online they ask for your name on your passport.

Where my photo is its my forename and surname on that page.

The next page is my Birth Cert name forname, Christian name and surname.

Which name do I use for booking a flight?

coylemj

Using terms like 'forename' and 'christian name' in the same sentence is confusing, for most people they are the same thing.

If your name is Patrick Joseph Murphy, I think what you're saying is that one page has 'Patrick Joseph Murphy' and the other only has 'Patrick Murphy'.

For a flight booking I would only use Patrick Murphy.

Jesus Shaves

Use your very first name and your very last name(surname).

Gatica

agree, first name_last name is fine I think. My OH usually puts in his middle name as well. No harm.
I think either one has been accepted by the airlines we've flown with, depending on whether he or I booked the flight.
We did have some confusion with an asian airline that had put Middle Name_first name in same textbox, so that's what I entered. Just had to prove to them after that the format was as they'd requested on the site.