Maintenance Margin Calculation
Updated on 2025/06/25
I. What is Maintenance Margin?
The Maintenance Margin (MM) is the minimum margin level a user must maintain for an open position. If unrealized losses reduce the position’s margin below this level, the system will trigger liquidation to prevent further losses and avoid account insolvency (i.e., "negative equity").
Larger positions entail higher risks. To protect the platform and all users during extreme market volatility, tiered Maintenance Margin Rates (MMR) are applied based on position notional value.
Generally:
- Higher notional values → Lower maximum leverage allowed → Higher MMR → More margin required.
- Each trading pair follows a predefined notional value-to-MMR tier table.
This article focuses on MM calculation rules. For tiered notional values, leverage limits, and MMR tiers, refer to this guide.
II. Calculating Maintenance Margin Rate (MMR)
The ratio of Maintenance Margin to position value is called the Maintenance Margin Rate (MMR). As position size increases, it gradually rises by tiering the position value.
This can be roughly understood through the following diagram:
V1,...,Vn represent the notional value ranges for different position tiers,
MMR1,...,MMRn represent the corresponding maintenance margin rates,
V represents the user's actual position value.
Example: ABCUSDT Perpetual Contract
Tier | Position Bracket (Notional Value in USDT) | Position Value Bracket（USDT） | Maintenance Margin Rate（MMR） |
|---|---|---|---|
1 | 0 - 1,000 | V1：1,000 | MMR1：0.5% |
2 | >1,000 - 3,000 | V2：3,000 | MMR2：1% |
3 | >3,000 - 6,000 | V3：4,000 | MMR3：1.5% |
4 | >6,000 - 10,000 | V4：7,000 | MMR4：2% |
5 | >10,000 - 15,000 | V5：15,000 | MMR5：2.5% |
Scenario: Trader Andrew opens a 1,000 ABC long position at 12 USDT with 10× leverage:
- Notional Value = 1,000 × 12 = 12,000 USDT (Tier 5)
- Initial Margin (IM) = 12,000 / 10 = 1,200 USDT
- Maintenance Margin (MM) = (1,000 × 0.5%) + (2,000 × 1%) + (3,000 × 1.5%) + (4,000 × 2%) + (2,000 × 2.5%) = 200 USDT
Result: The position can withstand up to 1,000 USDT (1,200 USDT – 200 USDT) in unrealized losses before liquidation.
III. Simplified Calculation via Maintenance Amount (MA)
To simplify the calculation of maintenance margin, the industry typically adopts an alternative approach by introducing Maintenance Amount (MA) to streamline computations.
This can be roughly understood through the following diagram: MA1,...,MAn represent the maintenance amounts corresponding to different position limits. Visually represented as the cumulative value of the dotted areas in the diagram that increase with higher position tiers, where MA1 is typically 0.
Thus,
Position Value = Position Quantity × Average Opening Price
Maintenance Margin (MM) = Position Value × Maintenance Margin Rate (MMR) - Maintenance Amount (MA)
Level n Maintenance Amount (MA) = Minimum value of Level n position limit × (Difference between MMR of Level n and Level n-1) + Level n-1 Maintenance Amount
The required Maintenance Margin Rate (MMR) and Maintenance Amount (MA) for each position limit level can be viewed on the leverage and margin parameters page.
The table below shows the requirements for Position Value and Maintenance Margin Rate corresponding to the BTCUSDT perpetual contract trading pair (not representing actual margin parameters).
Tier | Position Bracket (Notional Value in USDT) | Max Leverage | Maintenance Margin Rate（MMR） | Maintenance Amount (USDT) |
|---|---|---|---|---|
1 | 0 - 200,000 | 200X | 0.30% | 0 |
2 | >200,000 - 500,000 | 150X | 0.40% | 200 = 200,000 × (0.40%-0.30%) + 0 |
3 | >500,000 - 750,000 | 100X | 0.50% | 700 = 500,000 × (0.50%-0.40%) + 200 |
4 | >750,000 - 2,500,000 | 75X | 0.67% | 1,975 = 750,000 × (0.67%-0.50%) + 700 |
5 | >2,500,000 - 3,000,000 | 50X | 1.00% | 10,225 = 2,500,000 × (1.00%-0.67%) + 1,975 |
Scenario: Trader Bryan opens a 20 BTC long position at 100,000 USDT with 25× leverage:
- Notional Value = 20 × 100,000 = 2,000,000 USDT (Tier 4)
- IM = 2,000,000 / 25 = 80,000 USDT
Since the position value falls within the position limit of Level 5:
- MM = (2,000,000 × 0.67%) – 1,975 = 11,425 USDT
Result: The position tolerates up to 68,575 USDT (80,000 USDT – 11,425 USDT) in unrealized losses before liquidation.
IV. Locating Maintenance Margin in the Trading Interface
- Navigate to the Contract Trading Page → Check the Margin Info panel (bottom-right).
- Isolated Margin: Each position has an independent MM.
- Cross Margin: All positions share a single MM. Thus the maintenance margin applies to all cross margin positions.
