In MemberMouse, the amount charged at the time of purchase is called the Initial Payment or First Charge. Configuring a product with a trial period allows you to set the value of the first charge independently from subsequent charges. As a result, when a coupon that discounts the "first charge only" is applied to a product with a trial period, it is the trial price that is discounted.
This remains true even when you have configured a free trial on your subscription product. In this case, the initial payment is zero, and the coupon is applied to that amount. Since zero is the minimum value of a payment, applying a coupon to the first charge of a product with a free trial period has no effect.
Essentially you have two options when creating a coupon that is applied to a product with a trial period:
- Apply the coupon to the first charge. In the case of a product with a trial, the discount will be applied to the trial
- Apply the coupon to all charges and the discount will be applied to both the trial payment and the ongoing subscription payments
The checkout page will only show the discount on the amount that it is immediately charged, so that would be the trial amount. As a result, if your product has a free trial, then there is no immediate charge when checking out, so the total will be zero and there is nothing to discount. If you've created a coupon that applies to "all charges," the member can verify that their discount was applied in the Subscriptions section of the My Account page, where the discounted subscription billing rate will be displayed.