Cross Margin

Cross margin is a leverage mode where all open positions share a single collateral pool. Unlike isolated margin (where each position has its own locked margin), cross margin lets any position draw on the entire account balance to cover unrealized losses. The advantage is that a temporary drawdown on one position can be absorbed by collateral from other positions; the disadvantage is that a severe adverse move can liquidate the entire account at once.

When cross margin helps

Cross margin is most useful for hedged positions, correlated positions, or high-conviction directional trades where you want the position to survive larger temporary drawdowns. A trader running a hedged book (a BTC long and an ETH short, for example) benefits from cross because the two positions are typically correlated in the short term: a drawdown on one is offset by gains on the other, and shared collateral lets both ride out the noise without forcing a liquidation on either.

When cross margin hurts

Cross margin breaks the clean per-trade risk accounting that isolated margin enforces. Under isolated, a single 1% risk-per-trade plan caps the worst-case outcome of any one trade at 1% of the account. Under cross, a single severe drawdown can liquidate multiple positions sharing the collateral, consuming far more than 1% of the account. Beginners almost always benefit from staying on isolated until they have a specific reason to switch.

Cross margin and maintenance margin

Under cross margin, maintenance margin is calculated against the total notional of all open positions, not against each position separately. The liquidation event is a cross-portfolio liquidation: when total margin balance falls below the aggregate maintenance margin requirement, the exchange closes positions in priority order until the balance recovers. On Hex37, cross-margin liquidation runs on a separate leader process to ensure consistency across multiple ticker shards.

How to think about cross margin

• Start on isolated margin. The clean per-trade risk accounting is more valuable than the marginal collateral efficiency.
• Switch to cross only for specific scenarios: hedged books, correlated baskets, or high-conviction directional trades where you want explicit room for drawdown.
• If you switch to cross, recalculate your effective per-trade risk against the entire account. The 1% rule does not naturally extend to cross.
• Watch the aggregate margin display when running cross. The single-position display can look healthy while the portfolio total is approaching liquidation.