Each stacking rule includes a number of promotions that you want to treat as a group. Rules are intended to prevent simple combination strategies, for example to keep customers from combining BOGO offers with gift-with-purchase offers. In this example, you could add all your BOGO promotions to one stacking rule and all your gift-with-purchase promotions to another. Then you specify that the BOGO stacking rule cannot be combined with the gift-with-purchase rule.
Stacking rules have the following behavior:
Each promotion can be associated with only one stacking rule. If a promotion is already part of a stacking rule and you add it to another, Commerce Cloud automatically removes it from the first rule.
Within a stacking rule, promotions are applied in order, based on their priority. See Understand promotions for more information about promotion priority.
If an order qualifies for more than one promotion, and those promotions are in mutually exclusive stacking rules, the promotion with the highest priority is applied, and all other promotions the order qualifies for are skipped.
In addition to stacking rules, each promotion’s exclusion rules allow you to define individual promotions that cannot be combined with it. Exclusion rules override stacking rules. For example, if Promotion A excludes Promotion B, those promotions cannot be combined, even if they are in the same stacking rule or stacking rules that combine with each other. See Exclude promotions for more information.
If a promotion has already been applied to an order and that promotion excludes another promotion, the excluded promotion cannot be re-included by any promotions that apply later in the pricing process.