What Is a Maintenance Margin?

A maintenance margin is the minimum amount of equity that must be maintained in a margin account. The New York Stock Exchange (NYSE) and FINRA require investors to keep at least 25% of the total value of their securities in a margin account.

Although NYSE and FINRA require a 25% minimum, many brokerage firms may require a higher maintenance requirement—as much as 30% to 40%.

Maintenance margin is also called a minimum maintenance or maintenance requirement.

Understanding Maintenance Margins

A margin account is an account with a brokerage firm that allows an investor to buy securities including stocks, bonds, or options—all with cash loaned by the broker. All margin accounts, or purchasing securities on margin, have strict rules and regulations. The maintenance margin is one such rule. It stipulates the minimum amount of equity—the total value of securities in the margin account minus anything borrowed from the brokerage firm—that must be in a margin account at all times.

So if an investor has $10,000 worth of equity in his margin account, she must maintain a minimum amount of $2,500 in the margin account. If the value of her equity increases to $15,000, then the maintenance margin also rises to $3,750. The investor is hit with a margin call if the value of securities falls below the maintenance margin.

Margin trading is regulated by the federal government and other self-regulatory agencies in an effort to mitigate potentially crippling losses for both investors and brokerages. There are multiple regulators of margin trading, the most important of which are the Federal Reserve Board, the New York Stock Exchange (NYSE), and the Financial Industry Regulatory Authority (FINRA).


Maintenance Margin

Margin Accounts Versus Maintenance Margins

Investors and brokerage firms must sign an agreement before opening a margin account. According to the terms of the agreement set forth by FINRA, NYSE, and the Federal Reserve Board, the account requires a minimum margin be met before investors can trade on the account. The minimum or initial margin must be at least $2,000 in cash or securities.

The Federal Reserve Board’s Regulation T, or Reg T, mandates a limit on how much an investor can borrow, which is up to 50% of the price of the security purchased. Some brokerage firms require more than a 50% deposit from the investor.

Once an investor buys a security on margin, the maintenance margin goes into effect with FINRA requiring that at least 25% of the total market value of the securities be in the account at all times. Still, many brokers can require more as stipulated in the margin agreement.

If the equity in a margin account falls below the maintenance margin, the broker issues a margin call, which requires that the investor deposit more cash into the margin account bring the level of funds up to the maintenance margin or liquidate securities in order to fulfill the maintenance amount. The broker reserves the right to sell the securities in a margin account, sometimes without consulting the investor, to meet the maintenance margin. A Federal Call is a special kind of margin call issued by the federal government.

Maintenance minimums also eliminate some of the risk to the brokerage in case the investor defaults on the loan.

Maintenance margins, margin calls, Reg T, NYSE, and FINRA regulations all exist because margin trading has the potential to incur skyrocketing gains as well as colossal losses. Such losses are a huge financial risk, and if left unchecked can unsettle the securities markets, as well as potentially disrupt the entire financial market. (For related reading, see "Initial Margin vs. Maintenance Margin: What's the Difference?")

Key Takeaways

  • A maintenance margin is the minimum amount of equity required in a margin account.
  • NYSE and FINRA require an investor to keep 25% of the total value of equities in a margin account, but many brokerage firms require more.
  • The investor may be hit with a margin call if the account falls below the minimum and may be required to sell some or all the securities until the minimum is reached.