The Maintenance Margin Ratio (MMR) equals your Available Funds divided by the Maintenance Margin Requirement. It controls leverage limits under an active Margin+ agreement. You need an MMR of 12 or above to apply and must maintain above 10 after activation. A ratio below 10 for 12 hours or below five at any time triggers a Margin Call.
How is the Maintenance Margin Ratio calculated?
The Maintenance Margin Ratio (MMR) is your Available Funds divided by the Maintenance Margin Requirement. The formula is:
Maintenance Margin Ratio = Available Funds/Maintenance Margin RequirementAvailable Funds represent your total account equity minus any amounts already locked in initial margin or pending orders. The Maintenance Margin Requirement is the minimum margin needed to keep all open positions from liquidation, calculated as a percentage of each position’s notional value. BitMEX sets maintenance margin percentages per contract — for example, 10% for XBTUSDT and 5% for ETHUSDT.
The ratio controls how much leverage you can take in an active Margin+ agreement. A lower ratio means you have less available funds to cover the requirement tied to your open positions, meaning you are more leveraged. A higher ratio means you have more available funds to cover the requirement and hence are less leveraged. You can view your current Maintenance Margin Ratio at any time on your Margin+ page.
Meeting the required ratio thresholds is essential for both activating and maintaining your Margin+ agreement, as falling below them triggers a Margin Call process.
What are the MMR requirements for Margin+?
BitMEX enforces two distinct MMR thresholds depending on whether you are applying for Margin+ or already enrolled. Both thresholds exist to protect traders from immediate liquidation risk after committing funds.
When applying for Margin+
You must have a Maintenance Margin Ratio of 12 or above for BitMEX to process the funds drawdown. This buffer protects you from hitting a Margin Call shortly after activation. If your ratio sits below 12, you will need to reduce open positions, cancel pending orders, or deposit additional funds before BitMEX can process the application.
After your Margin+ is activated
Once enrolled, you must ensure your Maintenance Margin Ratio remains above 10 at all times. BitMEX monitors the ratio continuously. A Margin Call will occur under two conditions: if your ratio remains below 10 for a continuous period of 12 hours, or immediately if the ratio drops below five. During a Margin Call, BitMEX may reduce your positions to restore the ratio to a safe level.
Monitoring your MMR regularly is critical, especially during volatile market conditions when rapid price swings can erode available funds quickly. The practical impact of these thresholds becomes clearer when you calculate the ratio against real positions.
How does the Maintenance Margin Ratio work in practice?
Consider a trader with two open positions and a Margin Balance of 5,000 USDT:
- Position one: A long of 0.1 XBT on XBTUSDT (isolated 5x) at an entry price of 45,000 USDT. The notional value is 4,500 USDT. At a 10% maintenance margin rate, the maintenance margin requirement is 450 USDT.
- Position two: A long of one ETH on ETHUSDT (isolated 10x) at an entry price of 2,300 USDT. The notional value is 2,300 USDT. At a 5% maintenance margin rate, the maintenance margin requirement is 115 USDT.
The total Maintenance Margin Requirement across both positions is 450 + 115 = 565 USDT. Dividing the Margin Balance by this total gives:
MMR = 5,000 / 565 = 8.8A ratio of 8.8 is below the required threshold of 10. This means the trader would face a Margin Call if the ratio remained at this level for 12 hours. To avoid the call, the trader would need to either close one of the positions, deposit additional funds, or reduce leverage. Understanding how to raise the ratio is therefore a practical priority for any Margin+ user.
How can I improve my Maintenance Margin Ratio?
There are three direct ways to raise your Maintenance Margin Ratio, each targeting a different side of the formula. Since the ratio equals Available Funds divided by the Maintenance Margin Requirement, you can either increase the numerator or decrease the denominator.
Increase your Available Funds:
- Deposit additional funds (USDT, XBT, or other supported collateral) into your BitMEX account. Larger available funds raise the numerator of the ratio directly.
Reduce your Maintenance Margin Requirement:
- Close existing positions to remove their margin requirement from the denominator. Partially closing a position also reduces the requirement proportionally.
- Cancel open orders that reserve margin. Unfilled limit orders lock up available funds, so removing them frees margin and improves the ratio.
Adjust your leverage:
- Switch positions to lower leverage settings. Lower leverage increases the initial margin per position but reduces the relative maintenance margin burden against your total equity, improving the overall ratio.
BitMEX recommends monitoring the ratio, particularly during periods of high volatility when unrealised losses can erode available funds rapidly.