If the final trip price, including the tip, is lower than the voucher value, it will be covered by the voucher. However, if it exceeds the maximum voucher amount, the additional amount will be charged to your personal payment method. The app will show you how much this may be.
Some vouchers may not cover tips depending on the issuing organization’s configuration of the voucher.
Please view this article if you need more information on using vouchers from businesses.