Auctions: Bid Offer Spread

Bid–offer spread

The bid–offer spread (also known as bid–ask or buy–sell spread, and their equivalents using slashes in place of the dashes) for securities (such as stocks, futures contracts, options, or currency pairs) is the difference between the prices quoted (either by a single market maker or in a limit order book) for an immediate sale (ask) and an immediate purchase (bid).