A friend was asking me today whether the amount of the ticket will show if he used vouchers for that ticket? E.g. ticket value is $300 but he used a $300 voucher so it cost him nothing. Will the ticket show $0 or $300?

I think he wants to claim the ticket cost back from his company so he wanted to see if it displayed it. (I don't know whether that is ethically / legally allowed but I said I would ask for him). Thanks.