In finance, the margin is the collateral that an investor has to deposit with their broker or exchange to cover the credit risk the holder poses for the broker or the exchange. An investor can create credit risk if they borrow cash from the broker to buy financial instruments, borrow financial instruments to sell them short, or enter into a derivative contract.
Buying on margin occurs when an investor buys an asset by borrowing the balance from a broker. Buying on margin refers to the initial payment made to the broker for the asset; the investor uses the marginable securities in their brokerage account as collateral.
In a general business context, the margin is the difference between a product or service's selling price and the cost of production, or the ratio of profit to revenue. Margin can also refer to the portion of the interest rate on an adjustable-rate mortgage (ARM) added to the adjustment-index rate.
Key Takeaways
Margin is the money borrowed from a broker to purchase an investment and is the difference between the total value of an investment and the loan amount.
Margin trading refers to the practice of using borrowed funds from a broker to trade a financial asset, which forms the collateral for the loan from the broker.
A margin account is a standard brokerage account in which an investor is allowed to use the current cash or securities in their account as collateral for a loan.
Leverage conferred by margin will tend to amplify both gains and losses. In the event of a loss, a margin call may require your broker to liquidate securities without prior consent.
Understanding Margin and Marging Trading
Margin refers to the amount of equity an investor has in their brokerage account. "To buy on margin" means to use the money borrowed from a broker to purchase securities. You must have a margin account to do so, rather than a standard brokerage account. A margin account is a brokerage account in which the broker lends the investor money to buy more securities than what they could otherwise buy with the balance in their account.
Using margin to purchase securities is effectively like using the current cash or securities already in your account as collateral for a loan. The collateralized loan comes with a periodic interest rate that must be paid. The investor is using borrowed money, and therefore both the losses and gains will be magnified as a result. Margin investing can be advantageous in cases where the investor anticipates earning a higher rate of return on the investment than what they are paying in interest on the loan.
For example, if you have an initial margin requirement of 60% for your margin account, and you want to purchase $10,000 worth of securities, then your margin would be $6,000, and you could borrow the rest from the broker.