Entering and calculating order discounts
You can apply a discount at the line level or to the whole sales order. For whole order sales discounts, you can manually specify a whole order discount, or you can use a calculator. The discount amount is subtracted from the total sale amount for a new total or it is applied against the line for a new gross order margin. The difference is displayed in the Discount field in the Totals section on the Taxes & Totals page.
Use these instructions to enter a discount on a new order.