You can add a voucher during the booking process. Please note that it is not possible to add a voucher to a ride that has already taken place.
Via blacklane.com
At the final ride overview page of the booking process, click “Do you have a voucher code?”.
Enter your voucher code and click “Redeem”.
Via the app
At the confirmation page of the booking process, tap “Add voucher” on iOS, or the “⋮” symbol at the top of the page and then “Add voucher” on Android.
Enter your voucher code and confirm.