Market Orders are an order to buy or sell a stock at the best available price. Generally, this type of order will be executed immediately. However, the price at which a market order will be executed is not guaranteed. It is important for investors to remember that the last-traded price is not necessarily the price at which a market order will be executed. In fast-moving markets, the price at which a market order will execute often deviates from the last-traded price or “real time” quote. Not only is there a deviation from the “real-time” quote but the price it executes at is always the bid – ask price.
Details on Market Order:
Market orders guarantee execution as long as there is enough volume and a bid – ask price, and it often has low commissions due to the minimal work brokers need to do. Be wary of using market orders on stocks with a low average daily volume: in such market conditions the ask price can be a lot higher than the current market price (resulting in a large spread). In other words, you may end up paying a whole lot more than you originally anticipated! It is much safer to use a market order on high-volume stocks.