Cross margin is a derivatives account mode in which eligible collateral supports more than one position. The exchange applies its own rules for which balances, unrealized gains, and contracts share that collateral.
How Shared Collateral Changes Exposure
A profit on one position may increase equity available to support another position, depending on the venue and account type. A loss on one position can reduce the account equity available to support others. Cross margin can change liquidation outcomes while account-level risk remains.
Example
Suppose an account holds two positions and $2,000 in eligible collateral. If one position loses $300, the account has less equity available to meet maintenance requirements for the rest of its positions. The exchange may also count unrealized PnL, haircuts, fees, and risk tiers. This example shows the shared-collateral relationship, not a liquidation calculation.
Exchange Rules Matter
Portfolio margin, unified accounts, collateral haircuts, and auto-deleveraging can change the details. A trader should read the contract rules and monitor account equity rather than assume that the initial deposit defines the full balance at risk.
Compare Isolated Margin, Margin, Leverage, and Liquidation Price. See Hyperliquid's margining documentation for one venue's cross-account rules.