voucher
n. countablen. a piece of paper or a digital code that you can use to pay for something or get a discount.
n. a document or token that can be exchanged for goods or services as a substitute for cash. Often used in commercial contexts to represent a credit or a pre-paid transaction.
I have a voucher for a free coffee at the new cafe.
The airline provided a travel voucher to compensate the passengers for the long flight delay.
Gift vouchers have become a popular corporate incentive because they allow employees the flexibility to choose their own rewards while maintaining a fixed budget for the company.
From vouch + -er. The verb is from the noun.
Commonly used with the prepositions 'for' (a voucher for a meal) or 'against' (redeemable against your next purchase).