Introduction to Margin Modes (Cross vs. Isolated)

The choice between Cross Margin and Isolated Margin modes is a fundamental decision for traders utilizing leverage in crypto derivatives markets, such as trading futures contracts. Understanding these modes is a crucial component of the broader topic covered in Mechanics of Crypto Futures Trading. These settings determine how the available collateral in a trader's account is allocated to specific open positions, directly influencing risk exposure and the potential for liquidation.

Definition

Margin modes dictate the relationship between the margin assigned to an open futures position and the total available margin in the user's futures wallet.

Isolated Margin

Isolated Margin mode assigns a specific, fixed portion of the total account balance (the initial margin) to a single open position. This margin amount is isolated from the rest of the account equity. If the position moves against the trader and the margin dedicated to that position is exhausted (i.e., the position reaches its liquidation price), only the margin allocated to that specific trade is lost. The rest of the account balance remains unaffected and cannot be used to support the losing position.

Cross Margin

Cross Margin mode utilizes the entire available margin balance in the futures account as collateral for all open positions. If one position begins to suffer losses, the available margin from the entire account is used to cover the margin requirements of that position, delaying liquidation. While this can help prevent immediate liquidation on a single position, it means that significant losses on any position can potentially drain the entire account equity.

Why it matters

The choice between these modes directly impacts risk management:

Liquidation Threshold: Isolated margin allows a trader to define the maximum loss for a single trade. Cross margin exposes the entire account equity to the risk of any single large loss.
Margin Availability: In Isolated mode, unused margin in the account cannot be automatically drawn into a struggling position. In Cross mode, all equity acts as a buffer against margin calls across all active trades.

How it works

When using Isolated Margin:

The trader sets an initial margin amount for the trade.

If the market moves against the trade, the margin level drops.

Liquidation occurs when the position margin hits zero or the maintenance margin requirement cannot be met by the isolated collateral.

Cross Margin

The entire account equity is treated as collateral.

If one position requires more margin due to adverse price movement, funds are automatically drawn from the total account balance to cover the shortfall.

Liquidation only occurs when the total account equity falls below the required maintenance margin level for all open positions combined.

Practical examples

Example 1: Isolated Margin

BTC/USDT

If the position loses $200, the position will be liquidated. The remaining $800 in the account is safe.
If the trader opens a second position and isolates $300 for it, the first position's liquidation price remains unaffected by the performance of the second position, provided the second position does not exceed its $300 limit.

Example 2: Cross Margin

If the position loses $200, the account balance drops to $800, but the position remains open.
If the trader then opens a second short position that begins to lose money, the total losses are drawn from the $800 balance. Liquidation only occurs if the total account equity falls to near zero (minus the minimum maintenance margin).

Introduction to Margin Modes (Cross vs. Isolated)