Stacking rules prevent customers from taking advantage of unintended synergy among your promotions. (Coupon batches are another way of preventing customers from spreading promotions that you would prefer to target narrowly; see Creating Coupon Batches for information.)
The stacking rules user interface consists of two parts:
The stacking rule asset type allows you to define groups of promotions, which can then be combined with or excluded from use with other groups. You can also specify how many promotions within a group can be applied to any single order.
The promotion asset type allows you to specify individual promotions as usable with or excluded from use with other promotions.
Promotions are always applied in the following order: item discounts, order discounts, shipping discounts. Therefore, regardless of whether you are using stacking rule combinations or promotion inclusions and exclusions the following apply:
Item discounts can exclude both order and shipping discounts.
Order discounts cannot exclude item discounts.
Shipping discounts cannot exclude either item or order discounts.
The sections that follow describe how to use stacking rules and promotion inclusion and exclusion.
