Overview

Amazon calculates promotional discounts using the total amount of the original order, even when that order is broken into several shipments or sub‑orders. This rule stays the same whether the split is caused by the buyer’s checkout choices or by Amazon’s fulfillment logic, and it directly influences margin forecasts and performance reporting for sellers.

Key Points

• Discounts anchored to the full order subtotal — Regardless of how many parcels are generated, the discount amount is derived from the combined pre‑split total.
• Multiple promotions are evaluated separately — Each eligible promotion applies its own calculation to the original subtotal, and the resulting values are summed.
• Shipment division does not alter discount size — Whether an order is split into two boxes for different warehouses or the buyer selects separate delivery dates, the discount remains unchanged.
• Claim‑code promotions follow combinability rules — Coupon‑style codes may be limited to a single use per order or allowed to stack, depending on the seller’s configuration.
• Percentage‑based offers are especially sensitive — Because the discount is taken from the whole order amount, splitting the order does not reduce the percentage discount’s impact.
• Reporting reflects the original order, not each sub‑order — Sales and promotion reports list the discount once, tied to the parent order identifier.

How Discount Calculations Work

1. Identify the original order subtotal — Amazon first records the total price of all items before any split. Example: a buyer adds three items priced $30, $45, and $25, resulting in a $100 subtotal.
2. Apply each qualifying promotion independently — For every active promotion, Amazon computes the discount using the original subtotal. Example: a 5 % off coupon yields $5.00, while a “$15 off $75” promotion yields $15.00.
3. Aggregate the individual discount amounts — The system adds all calculated discounts together to produce a single total discount.