back order

(industrial engineering) An order held for future completion. A new order placed for previously unavailable materials of an old order.

Seller's order for goods from a supplier that have been requested by the seller's customer but are not in the seller's current inventory. A back order is an open obligation (of the supplier to ship and of the buyer to accept) until the merchandise becomes available and the transaction can be completed.

Customer's order that cannot be filled at the present time usually because the merchandise is not currently in stock. As soon as the product is available, it will be shipped to the customer. There usually exists a company policy of how long an unshipped order remains an order without some sort of confirmation or communication. An excessive amount of back orders may indicate to the accountant that poor inventory planning exists.

An item not currently in stock but to be sold or delivered when it becomes available, as in We don't have the shoes in white, but we can make them a back order. The verb back-order means "to obtain such an item," as in The furniture store is going to back-order the sofa for us.