If multiple, unpaid order line items exist between the same buyer and seller, the buyer or seller has the option of combining these multiple order line items into one order. This is known as a Combined Invoice order (formerly called combined payment order).

Sellers can specify how packaging/handling cost is to be determined globally for orders via the CalculatedHandlingDiscount field of SetShippingDiscountProfiles. Shipping discounts are set in the CalculatedHandlingDiscount, CalculatedShippingDiscount, and FlatShippingDiscount containers and will apply towards eBay orders if the combined payment option is enabled. Refer to SetShippingDiscountProfiles.CalculatedHandlingDiscount.DiscountName.

For additional information about Combined Invoice orders, refer to Combined Invoice in the Manage and Fulfill Orders section of this guide.