Moderator, Iberia Airlines, Airport Lounges, and Ambassador, British Airways Executive Club
Join Date: Feb 2010
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Posts: 63,735
Online it's only one voucher per booking, but you don't have to use all the booking up in one go, anything unspent on the eVoucher can be used in the next booking. I think that contact centres can add several eVouchers to one booking. If you have a number of future bookings it's get easy since you can just patch one at a time online and then use the residual amount in a mixed eVoucher and credit card booking.