It is possible for a new customer coming through your marketplace listing to use a coupon code.

You can influence the promotion a customer uses by publishing a special marketplace coupon code to your listing. To do this, navigate to the "Marketplace" button in your merchant dashboard. From here, you can select any coupon codes you've created to publish on your marketplace listing.

Keep in mind, the 10% Marketplace Fee is always based on the transaction amount (not your retail price). Learn more about the marketplace fee.