Discount stacking

In plain words

Discount stacking is what happens when more than one discount lands on the same order. A sale price meets a subscribe-and-save discount. A welcome code is used on a bundle that is already reduced.

Each discount was set on its own, against a full-price order. Stacked, the second applies to a price the first has already cut, and the order's fixed costs have not moved at all. An order can be comfortably profitable under either discount and close to break-even under both.

Formula

• Stacked price = price × (1 − discount A) × (1 − discount B)
• Two discounts applied in turn come to less than their sum: 20% then 10% is 28% off

Worked example

A 20% sale takes the $40.00 bag to $32.00 and leaves $7.99 of margin. A 10% subscription discount alone leaves $11.68.

With both, one after the other, the bag sells for $28.80 and the engine puts the order's margin at $5.04, or 17.5%.

Computed by the margin engine in Offer Suite's own code, in whole cents, from a $40.00 bag of coffee with a $12.00 unit cost.

Stacking is not adding the percentages

Discounts applied in turn multiply, so 20% and 10% make 28%. And some discounts do not combine at all: a platform may apply only the larger, or refuse the second. What a customer is really charged is decided at checkout, so check it there.

Using it

List every discount that can meet on one order, and price the worst case on your smallest order. Then decide which combinations to allow. Check the result in a real cart: which discounts combine is a matter of how each is set up, and it is easy to get a different answer from the one you planned.

In Offer Suite

Offer Suite verifies an offer on a real cart before it goes live: the price each option promises is compared with what the store actually charges, so a discount that stacks, or fails to, shows up before a customer sees it.

Source: Offer Suite's publish verification.