<aside> ⚠️ Perpetual futures are currently in limited access. Please contact [email protected] for more information.

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Balance

The perpetual futures exchange currently only accepts USDC for collateral and settlement. These funds are held in a different internal wallet from the spot and cross exchanges: you must transfer funds internally to your margin wallet before trading, and any funds left in the main exchange are not at risk from perps trades. Currently, all trading is cross-margin, so funds held in the margin wallet are used as collateral for all positions. The exchange provides the following numbers to determine an account’s balance:

• Wallet Balance: After a margin account transfer, the funds reflect in your Wallet Balance. This balance also shows the results of realized PnL from trades, funding fee payments, receipts, and exchange fees.
• Margin Balance: This is the sum of Wallet Balance and Unrealized PnL. It's used when calculating leverage and margin ratio.
• Used Margin: This is the balance reserved as collateral for positions and resting orders, summed across all markets. For each market, this is calculated as max(long used margin, short used margin)
  • A position contributes (position base size * mark price / market max leverage) to the used margin in its direction. For example, a position of 1 BTC-USD.P with a mark price of $60,000 in a market with 10x max leverage would use $6,000 of margin.
  • A resting limit order contributes (order remaining size * limit price / market max leverage) to the used margin in its direction.
  • This allows placing a limit order to close a position without requiring any more margin: If a long position is using $6,000 of margin, used margin for that market will equal max($6,000, $0,000) = $6,000. After placing the short limit order, used margin will equal max($6,000, $6,000) = $6,000.
• Available Margin: This is the balance available for placing new orders, equal to Margin Balance - Used Margin. Larger orders that reduce a position or hedge resting orders may still be allowed.
• Withdrawable Margin: This is the balance that can be withdrawn. If there are no positions or resting orders, this will be equal to the Margin Balance.

In addition, the exchange provides several measures of risk for accounts:

• Maintenance Margin Requirement: This is the total maintenance margin requirement for all open positions, equal to the sum of each position’s notional value multiplied by its contact’s Maintenance Margin Rate. The liquidation process is triggered when an account’s Margin Balance falls below its Maintenance Margin Requirement.
• Margin Ratio: This is a gauge of how close the account is to liquidation. At 0, there are no positions. The account is at risk at values above 0.5 and liquidation begins at a value of 1. It returns 9999 if the margin balance is negative or zero, and 0 if both the margin balance and maintenance margin are zero.
• Account Leverage: This indicates the account's leverage, calculated as the notional value of all positions divided by the Margin Balance. The account won’t be allowed to increase their position any further when account leverage reaches a contract’s Max Leverage.

Endpoints are available to create margin transfers, list margin transfers, and view account balance.

Balance validation and max position size

When placing an order, there are two checks that must pass.

• Each market has a **Maximum Position Size.** When placing a new order, we simulate execution of the order. The base size of the resulting position, plus the sum of the remaining sizes of all resting orders in the same direction as the position, must be less than or equal to the maximum position size.

  For example, assume the position limit for BTC-USD.P is 3 contracts. Consider an account with…

  • A resting order to buy 1 BTC-USD.P at $60,000
  • A resting order to sell 1 BTC-USD.P at $60,000
  • A position long 1 BTC-USD.P

  A market order to buy 1 BTC-USD.P would succeed, as that would result in: 2 (long position size) + 1 (long resting orders total) = 3 BTC-USD.P

  But a market order to buy 2 BTC-USD.P would fail: 3 (long position size) + 1 (long resting orders total) = 4 BTC-USD.P

  In the other direction, an order to sell 2 BTC-USD.P would succeed: 2 (short position size) + 1 (short resting orders total) = 3 BTC-USD.P

  But a short order to sell 3 BTC-USD.P would fail: 3 (short position size) + 1 (short resting orders total) = 3 BTC-USD.P

• When placing a new order, we simulate execution of the order. The resulting **used margin** must be less than the resulting margin balance.

Positions

When a bid and ask order match, they create an opposite positions on each account: the account on the bid side will enter a long position and the account on the ask side will enter a short position in the same size. Additional matches will update these positions to the new net values, so buying 2 BTC worth of perpetual futures and then selling 1 BTC worth will result in a net position of 1 BTC long.