How Futures Margin Works, in Plain English

The word “margin” causes more confusion in finance than almost any other, because it means two different things depending on what you trade. In a stock account, margin is a loan from your broker, and you pay interest on it. In a futures account, margin is a deposit. Nobody lends you anything, and no interest is charged.

Investors who have traded stocks for years often assume futures margin works the same way. It doesn’t, and the differences decide how much you can make, how much you can lose and how fast it happens. Here is how futures margin works, step by step.

A deposit that guarantees performance

When you buy or sell a futures contract, you agree to a price for something in the future. You don’t pay the full value of the contract up front. Instead, you post margin: a good-faith deposit, sometimes called a performance bond, that shows you can cover losses as the price moves.

Because the money stays yours and sits in your account as collateral, there’s no interest to pay on it. That makes futures margin very different from the stock margin loans I covered in Your Broker May Be Charging You Double to Borrow, where the rate you pay can run from about 5% to more than 12% a year depending on the firm.

Who sets the numbers

The exchange sets two levels for every contract:

• Initial margin: the amount you need in the account to open a position.
• Maintenance margin: the lower amount you must keep in the account while the position stays open.

Brokers can require more than the exchange minimum. Many also set lower “day-trade margins” for positions opened and closed within the same session. Those day-trade levels are each broker’s own choice, and they apply only if you’re flat before the session ends. Hold the position past that point and the broker’s full initial and maintenance margin applies.

A low day-trade margin can make a position look cheap to open. It lowers the deposit, while the exposure, and the dollar swing for every point the market moves, stay exactly the same.

Marked to market, every day

This is the mechanic that surprises stock investors most. Futures positions are marked to market daily. At the end of each trading day, gains and losses settle into your account as cash. You don’t wait until you close the trade to see the money move.

Here is a hypothetical example with one Micro E-mini S&P 500 contract, which moves $5 per index point:

1. Day one: A trader buys one contract at 7,000. The day settles at 6,980. The account is debited $100 (20 points × $5).
2. Day two: The contract settles at 7,010, up 30 points. The account is credited $150.
3. Day three: The trader sells at 7,010. Over the life of the trade, the net result is a $50 gain, which is the 10-point rise from 7,000 times $5, minus commissions and fees.

The final number is the same as it would be without daily settlement. What changes is the path. Losing days pull real cash out of your account that same evening, and that cash is what stands between you and a margin call.

The margin call

If losses drag your account equity below the maintenance level, you get a margin call. You’ll need to deposit more money or reduce the position. Brokers can and do liquidate positions to bring an account back into line, and in a fast market they may not wait for you to respond.

With trading running nearly 23 hours a day, a position can move a long way while you sleep. If you hold futures overnight, assume your broker may close you out before you have a chance to respond.

How much leverage you’re really using

The deposit is a fraction of what the contract controls, and that gap is the leverage. Take the S&P 500 at 7,000 and look at a 1% move, which is 70 points:

A 1% day in the index is unremarkable. On one E-mini, it moves your account by $3,500. Since the deposit is well below the full contract value, a few bad days in a row can consume it entirely, and losses can exceed what you deposited. When that happens, you owe the difference.

The smallest contracts make this easier to live with. CME launched E-nano futures in August 2026 partly because, with indexes at record highs, even Micros had become large for small accounts. I explain the new contracts in E-Nano Futures: Wall Street’s Smallest Index Contract, Explained. One practical note: CME hadn’t finalized E-nano margins before launch, so check what your broker requires.

What margin costs you, and what it doesn’t

Since futures margin carries no interest, your trading costs come from elsewhere:

• Commissions, charged per contract, per side. A round trip is two sides.
• Exchange, NFA and clearing fees, also per contract. NinjaTrader, for example, lists $0.36 plus $0.19 per side on the Micro E-mini S&P.

Commissions vary widely. On a Micro E-mini, on standard plans they run from $0.25 per side at Interactive Brokers to $2.25 per contract at Schwab, per its futures FAQ. For someone doing 100 Micro round trips a month, that’s roughly $50 at the cheapest brokers and about $450 at Schwab. The BrokerNimble futures commission table lists rates for 14 brokers.

Where your deposit actually sits

Futures accounts aren’t covered by SIPC, the program that protects stock accounts up to $500,000 if a broker fails. Instead, customer funds in futures accounts are held in segregated accounts under CFTC rules, kept apart from the firm’s own money. That’s a meaningful protection, and it works differently from SIPC, so read your broker’s disclosures on it.

Five sensible ground rules

1. Size from the exposure. Ask how much stock market exposure the position represents, then decide whether you’d hold that much in stocks.
2. Keep extra cash in the account. Posting only the minimum means a single ordinary down day can trigger a call.
3. Treat day-trade margin as a convenience. It applies only while the session lasts.
4. Use stops and know your broker’s liquidation policy. Read it before you need it.
5. Start smaller than you think. Micro and E-nano contracts exist for a reason.

Futures are one tool among many in a brokerage account. My full guide to choosing and using a broker covers how they fit with margin, cash and everything else.

Disclosure: Peter Agro runs BrokerNimble.com, an independent broker comparison site that plans to join broker affiliate programs and may earn referral fees in the future. Figures were checked in October 2026 and change often; confirm current terms with the provider. This article is for information only and is not investment, tax or legal advice. Futures, margin and options trading involve substantial risk of loss, including losses greater than your deposit.