What it means
When an investor buys shares on margin, the broker lends part of the purchase price and the investor puts up the rest. Regulation T sets the minimum share that the investor must pay with their own money at the time of the purchase.
If the investor's own contribution falls short, the broker issues a federal call. The call is usually met by depositing cash or by selling securities within a short time limit set by the rules and the broker.
If the customer fails to act, the broker can sell positions to bring the account into line. This is why a federal call is more than a polite reminder.
A federal call is different from a maintenance call. A maintenance call happens later, when falling prices push the account value below the minimum equity level that the broker or exchange requires.
A federal call is about the starting position, and a maintenance call is about keeping the position afterwards. For a finance professional, the idea is useful because margin is a form of leverage, which means borrowing to increase the size of an investment.
Leverage magnifies gains but also losses, and a federal call is one of the few controls that limit it at the start. Treasury teams that hold margin accounts for hedging should understand when a call might be triggered.
The exact initial margin percentage is set by the Federal Reserve Board and can be changed, so the rule should be checked rather than assumed. Brokers may also apply their own stricter standards, so a customer can receive a call even when the legal minimum has been met.
In practice
Real-world examples.
Example
A retail investor buys $40,000 of technology shares with $14,000 of her own cash. At a 50% initial margin rule she needs $20,000, so the broker issues a federal call for $6,000. She transfers the money the next morning and keeps the position. Afterwards she asks the broker to send her a text message on any day that a purchase leaves her short.
Example
A small family office buys $200,000 of shares on margin before a holiday weekend. A transfer from its bank is delayed, so the account is $15,000 short of the requirement. The office sells a small holding to meet the call rather than risk a forced sale of its whole position.
Example
An independent financial adviser opens a margin account for a client who plans a $60,000 purchase. She explains in advance that $30,000 must be in the account, which prevents a surprise call. The client wires the funds on the trade date. The trade settles normally, and the adviser notes the funding steps in the client file for future purchases.
Formula
Calculation
Federal call = required initial equity - equity the customer has deposited
Required initial equity = purchase price x initial margin percentage
Suppose an investor buys $20,000 of shares and the initial margin percentage is 50%, which is the figure used here as an illustration. Required equity = 20,000 x 0.50 = $10,000. The investor has deposited only $6,000, so the federal call = 10,000 - 6,000 = $4,000. The investor can meet the call by depositing $4,000 in cash or by selling securities worth enough to cover the gap.Case study
Seen in the real world.
Brightwater Investments is an illustrative, fictional boutique firm whose partner, Priya, uses margin to build positions for her own account. One Monday she buys $120,000 of shares expecting a bonus payment to arrive the same week.
The payment is late, and the account holds only $48,000 of her own money against a $60,000 requirement. The broker issues a federal call for $12,000, and Priya must either deposit cash or sell part of her holding within the time allowed.
She sells $12,000 worth of a smaller position, which clears the call, and then updates her cash planning so that her own contribution is in place before the trade date. The illustrative lesson is that margin buying needs the cash ready on the day, not after it. She also keeps a small buffer above the minimum so that a small price move cannot catch her short.
Watch out
Common mistakes.
- Confusing a federal call with a maintenance call, which relates to a falling account value after the purchase.
- Assuming a call can be ignored for several days with no consequence, when the broker may sell positions to cover it.
- Believing the margin percentage is fixed forever, when the Federal Reserve Board can change it.
Questions
People also ask.
What is Regulation T?
It is the Federal Reserve rule that governs credit that brokers and dealers may extend to customers for buying securities.
How can a federal call be met?
By depositing cash, depositing fully paid securities or selling securities in the account to cover the shortfall.
Can a broker be stricter than the rule?
Yes, brokers can set higher requirements, so a call may arrive even if the legal minimum is met.
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