You can offer postage discounts to buyers when they buy more than one item at a time. To set up postage discounts for combined payments, go to Postage and Discount Preferences in the eBay Preferences section in My eBay. Within the preferences, turn on the postage preference for "Allow buyers to combine items."
When a buyer purchases one of your items, a message will appear showing the availability of a discount if the buyer buys more items from you and combines the postage. If payments for more than one item are combined and your postage discounts preference is activated, eBay will automatically calculate the postage discount and deduct it from the total cost of the purchase when buyers initiate payment. The calculated postage savings will be shown to your buyers when they complete payment. Buyers will need to note that if they want to combine their invoice they can only checkout once they have won all their items.
When you list an item that you want to exclude from the postage discount, deselect the "Apply a postage discount if the buyer purchases multiple items from me" checkbox option on the Sell Your Item form. A buyer may still send a combined payment to you, but the postage discount will not be applied.
Note: We’ll soon be discontinuing the postage insurance option.