You may enter a limit order regardless of whether a quote reflecting other orders is available. The quotations to buy and sell may differ significantly from the regular session's prices, including the closing prices and the opening prices the next morning. Risk of Communications Delays or Failures. Delays or failures in communications due to a high volume of orders or communications, or due to other computer system problems, including Internet delays, may cause delays in, or prevent, the execution of your order. Risk of Lower Liquidity.
Liquidity refers to the ready availability of securities for trading.
Generally, the more orders available in the market, the more liquid that market is. Due to limited trading activity in the extended-hours trading sessions, the liquidity in these sessions may be significantly less than during regular market hours. Lower liquidity may prevent your order from being executed in whole or in part, or from receiving as favorable a price as you might receive during regular trading hours. In addition, lower liquidity means fewer shares of a given security are being traded, which may result in larger spreads between bid and ask prices and volatile swings in stock prices. Risk of Trading Halts.