What is a Market Order - Trading in US?

A market order is an order to buy or sell, and has no price limit specified at the time of entry. A market order is executed at the best prices available on the opposite side of the order book.

A market order can match with as many orders as possible on the opposite side of the order book, up to the quantity carried by the market order.

At the point of order entry during Main Trading phase, a market order will be immediately rejected if there is no order queuing on the opposite side of the order book.