What Is Maintenance Margin in Trading? A Beginner's Guide

Maintenance margin is the minimum amount of account equity you must maintain to keep an open leveraged position active. If your account equity falls below this threshold because of adverse market movements or holding costs, your broker may issue a margin call or automatically close your positions.

For derivative traders, understanding what maintenance margin means in practice is important when managing trades through temporary price fluctuations. Holding leveraged positions requires careful monitoring of account equity, as overnight financing charges and changing market spreads can reduce your available buffer even when the underlying asset price remains relatively stable.

What Is Maintenance Margin?

So, what does maintenance margin mean for your day-to-day trading? It's the equity line you must stay above to avoid a forced close-out.

The technical maintenance margin meaning refers to the minimum amount of account equity required to support open leveraged positions. Equity represents your account balance adjusted for real-time unrealised profits and losses. Unlike notional value — which represents the full market exposure of your position — maintenance margin is a threshold used to determine whether you have sufficient equity to keep leveraged positions open.

When you trade financial contracts using leverage, you can open positions with a larger market exposure than the cash deposited as margin. However, your broker requires sufficient account equity to cover potential losses. Maintenance margin provides a minimum threshold for this purpose.

If the market moves against your position, floating losses reduce your total account equity. When your equity falls below the maintenance margin threshold, your broker may take action to limit further financial exposure.

Initial Margin vs Maintenance Margin: Key Differences

To manage margin risk effectively, you need to understand the difference between initial margin and maintenance margin. Both relate to the funds required to support leveraged positions, but they serve different purposes at different stages of a trade.

Initial margin is the upfront deposit required to open a position. It is calculated as a percentage of the trade's total value. Maintenance margin, by contrast, is the minimum ongoing equity required to keep that position open. The maintenance margin requirement is generally lower than the initial margin requirement.

Because leverage increases exposure to both gains and losses, even a relatively small adverse price movement can reduce your available equity quickly. Understanding how initial and maintenance margin interact can help you avoid opening positions so large that a small market movement puts your account close to its margin threshold.

How Maintenance Margin Works in CFD Trading

With maintenance margin explained in these terms, you can see why brokers monitor equity in real time rather than only at the point a trade is opened.

To monitor your margin position, you need to understand how unrealised profits, unrealised losses and ongoing trading costs affect your total account equity.

Account equity can be expressed using this simple formula:

Account Equity = Cash Balance + Floating Profit − Floating Loss

Your margin level percentage indicates the relationship between your account equity and margin requirement:

Margin Level Percentage = (Account Equity ÷ Margin Requirement) × 100

Consider an example where you deposit $1,000 into a trading account. You open a leveraged position requiring $400 in initial margin, while the broker sets the maintenance margin threshold at $200.

If the market moves against your position and the trade develops an unrealised loss of $750, your account equity falls to $250 ($1,000 balance minus the $750 floating loss). Because $250 remains above the $200 maintenance margin requirement, the position stays open. However, if the market moves further against you and the unrealised loss reaches $850, your account equity falls to $150. As $150 is below the $200 threshold, your broker may take action.

Trading costs can also reduce your account equity over time. Retail traders can be caught out by overnight fees or wider spreads around weekend trading periods, which can reduce account equity and contribute to an unexpected margin call.

Daily financing charges reduce your account balance, gradually shrinking the equity buffer available to support your open positions.

What Happens When Equity Falls Below Maintenance Margin?

When your account equity falls below the maintenance margin level, your broker may take action to limit further risk. Traditionally, a margin call referred to a direct notification asking the trader to deposit additional funds or close positions manually.

In modern retail CFD trading, much of this process is automated. Regulatory protections, such as those established under the Financial Conduct Authority (FCA) and European Securities and Markets Authority (ESMA) regulatory frameworks, include a mandatory 50% margin close-out rule. Once account equity reaches the relevant regulatory close-out level, the broker's platform may begin automatically closing positions.

During automatic close-out, the broker closes open positions according to its liquidation procedures until the account meets the required margin conditions.

Stop-loss orders do not always prevent a position from reaching the maintenance margin threshold. During periods of extreme volatility or illiquid market openings, prices can gap beyond a stop-loss level. This can result in slippage, where the trade is executed at a different — and potentially significantly worse — price than requested.

How to Manage Your Maintenance Margin Threshold

Keeping account equity comfortably above the maintenance margin threshold requires active risk management rather than simply monitoring your balance.

• Maintain a Capital Buffer: Avoid committing all your available account funds to initial margin requirements. Keeping unused funds in your account provides a buffer against adverse market movements.
• Size Positions Appropriately: Use position sizes that are proportionate to your overall account balance. Smaller positions reduce the effect that floating losses can have on total account equity.
• Use Stop-Loss Orders: Stop-loss orders can help limit losses before adverse price movements reduce your account equity towards the maintenance margin threshold.
• Account for Holding Fees: Include overnight fees and weekend holding costs in your risk calculations, particularly when keeping positions open across multiple trading sessions.

Avoid adding more capital to a losing position solely to delay a margin call without reassessing the underlying risk. If the position continues to move against you, committing additional funds can increase your total financial loss.

Conclusion

Put simply, what is maintenance margin? It's the equity floor your broker sets to keep a leveraged position open.

Understanding how maintenance margin works can help you manage position sizes and reduce the risk of automatic close-outs. Monitoring account equity, leverage and ongoing holding costs is particularly important because each can affect how close your account is to its maintenance margin threshold.

Trading CFDs carries a high risk of losing money rapidly because of leverage. Understanding how margin works is therefore important before putting real capital at risk. Margin requirements should be treated as risk limits rather than targets for maximising position size.

If you are new to leveraged products, reviewing how leverage in trading affects account equity under different market conditions can help you develop a more structured approach to managing trading risk.