A technique involving the purchase of securities with borrowed money. The amount of collateral needed to hold these positions can vary between brokers and industries. Some brokers require using the security itself as collateral, while others require a minimum leverage payment to maintain the position. It is usually done using a margin account at a brokerage and subject to additional regulations by the SEC, CFTC, or any other regulatory body.

Margin trading is used by speculators to amplify profits as the price of the security moves in their favor. However, margin buying can also amplify the losses if the price of the security moves against the trader. For this reason, trading margin is considered by many as a double-edged sword.