Maintenance Margin
Maintenance margin is the minimum equity you must keep to hold a margin position. Learn how it differs from initial margin and why falling below it triggers a margin call.
Maintenance margin is the minimum amount of equity you must keep in your account to hold a margin position open. It is the floor: dip below it, and your broker issues a margin call demanding more money or closing your trade. It is the ongoing collateral requirement, distinct from the amount needed to open the trade.
The word "maintenance" is the clue, it is what you must maintain to stay in the game. Let me show you how it works.
The Floor You Must Stay Above
Opening a margin trade requires an amount called initial margin. But the requirement does not end there. To keep the position open, you must keep your equity above a lower level, the maintenance margin, at all times.
Think of it like the minimum balance on a special bank account. You needed a certain deposit to open it, but you also have to keep at least a set amount in it or the bank steps in. As long as your equity stays above the maintenance floor, you are fine. If a losing trade eats into your equity and it slips below that floor, the broker acts.
Initial vs Maintenance Margin
The two margin levels do different jobs, and mixing them up causes confusion.
Initial margin is what you need to open a position, the larger, upfront collateral. It is checked at entry.
Maintenance margin is what you need to keep the position open, a lower level checked continuously afterward. It is the ongoing floor.
The gap between them is your cushion. When you open a trade, your equity sits above the maintenance floor, giving room for the position to move against you before trouble starts. As losses mount and your equity falls toward that floor, the cushion shrinks. Cross the floor, and the broker issues a margin call.
Why It Matters
Maintenance margin is the mechanism that decides when a losing position forces your hand.
It sets your breaking point. Knowing your maintenance requirement tells you how far a trade can move against you before you are in trouble. That is essential for anyone selling options or using leverage, where a sharp move can burn through the cushion fast.
It can force a sale at the worst time. If you cannot meet a margin call, the broker liquidates your positions, often right when prices are ugly. Keeping a comfortable buffer above the maintenance floor, rather than trading at the edge of your margin, is how disciplined traders avoid a forced exit. Some large accounts qualify for portfolio margin, which sets these requirements based on total portfolio risk instead.
- Maintenance margin is the minimum equity to keep a position open.
- It is lower than initial margin and checked continuously.
- Falling below it triggers a margin call.
- Keep a buffer above the floor to avoid a forced liquidation.
Pop Quiz
Three quick questions to see what stuck. Pick an answer and the explanation shows up right away.
What is maintenance margin?
It is the ongoing equity floor. Stay above it to keep the position; fall below and the broker acts.
How does maintenance margin differ from initial margin?
Initial margin is the upfront requirement to enter; maintenance margin is the lower, ongoing floor.
What happens if your equity falls below the maintenance margin?
Breaching the floor triggers a margin call, demanding more collateral or a forced liquidation.
Bottom Line
Maintenance margin is the equity floor you must stay above to keep a leveraged or short position open. It is lower than the initial margin you needed to enter, and it is checked continuously, so a losing trade that eats through your cushion can push you below it.
Cross that floor and the broker issues a margin call, possibly liquidating you at the worst moment. Knowing your maintenance requirement and keeping a buffer above it is how you stay in control instead of being forced out.
Keep going: the broader concept is margin requirements, the alarm it triggers is the margin call, and the advanced system is portfolio margin.