Single-purpose vouchers
A voucher is single-purpose when, at the moment you sell it, you know where the supply will take place and how much VAT will be due, and everything it can buy is taxed at one rate. VAT is due in the VAT period in which the voucher is sold. If the customer never uses it, Revenue says no adjustment can be made.
A voucher for one specific treatment, or for a service that is all taxed at one rate, is likely to be single-purpose.
Multi-purpose vouchers
Any voucher that is not single-purpose is multi-purpose. A money voucher for a hotel that can be spent on rooms, food and drink, which are taxed at different rates, is a typical example. VAT is only due when the voucher is redeemed, based on what it is spent on. If it is never redeemed, no VAT is due.
What this means for your records
For multi-purpose vouchers, you need to know when each voucher was used and what it paid for, including partial redemptions. For single-purpose vouchers, you need the sale date and value. Either way, keep outstanding voucher balances visible so your accountant can see what has been sold and not yet used.
Bronora records each sale and each redemption, including partial use, and shows outstanding voucher value in the merchant workspace with an export. It does not decide which VAT treatment applies to your vouchers. Agree that with your accountant, then set up your products to match. The voucher expiry guide covers how long vouchers must stay valid.