We don’t recommend using an exchange as a wallet for paying invoices at Gift Off. They often include unnecessary additional fees and have lower security protections than other wallets.
If you do decide to pay through an exchange, you must add-on additional funds to cover exchange withdrawal fees in addition to the normal miner fees. This means adding more bitcoin than what is displayed on the checkout. Failure to cover exchange fees will result in an underpaid invoice and might require a refund (minus any network transaction fees).