Create coupons from the Marketing > Coupons menu. Coupons are simply unique codes that you create to give to your customers and for them to hand-in during checkout. It’s a useful way to limit a promotion given out to only those who have the code (e.g. give 10% discount to only users who read your newsletter).
Coupons by themselves do not perform any action. They need to be associated to a marketing promotion or place order action rule. During checkout, the promotion and place order action rules can trigger against the collected coupon codes and determine what discount or action to take. Only promotion types that occur during checkout stage can trigger against coupon codes collected (i.e. Sales Order Detail, Shipping, Handling, Tax promotion types). Please see Promotions section for more information. Place order action rules can also trigger against the collected coupon codes and perform actions such as assigning a security role. See Actions section for more information.
You can control when a coupon is valid using the Start and Stop date fields. You can also limit the number of available coupons using the Inventory field. The available coupons will be decremented by one every time a coupon is remitted.