extended hours trading

A period of electronic trading that takes place before or after the regular trading session for an exchange. At one time, only orders placed by institutional investors could be placed and filled during extended hours trading. Today electronic communications networks (ECNs) make it possible for market makers and brokerage firms participate in pre-market and after-market trading on a voluntary basis. Individual investors can also buy and sell stocks during extended trading hours by choosing a broker that provides access. See Pre-Market; After Hours Trading (AFT).