Cross Margin vs Isolated Margin

Isolated margin

In an isolated-margin setup, the margin assigned to a position is separated from other available balances according to the venue's rules.

This can limit how much additional account collateral is automatically exposed to that position.

Cross margin

Cross margin allows a broader pool of eligible account collateral to support positions. Profits and losses from multiple positions can therefore interact through shared equity.

The trade-off

Isolated margin can make the capital allocated to one position easier to contain. Cross margin can provide more buffer against liquidation but can expose more eligible account equity to losses.

Margin mode does not define acceptable risk

Neither mode automatically makes a trade safe. A trader still needs to define position size and maximum acceptable loss.

Implementation differs by venue

Eligible collateral, auto-add-margin features, portfolio margin and account-level calculations differ substantially between platforms.

The key difference is the collateral boundary

Isolated margin generally limits the collateral assigned to a particular position or margin pool. Cross margin generally allows a broader pool of eligible collateral to support positions according to the venue's rules.

This changes where losses can draw support from; it does not make either mode inherently safe.

How cross margin can connect positions

With shared collateral, losses and margin requirements from one position can reduce the resources available to support another. The advantage is that unused eligible collateral may provide additional buffer.

The trade-off is that a wider portion of the account can become exposed to the same margin system.

What isolated margin does—and does not—do

Isolated margin can create a clearer collateral boundary, but the position can still be liquidated when its assigned margin becomes insufficient. Adding collateral to that position changes the amount exposed.

Margin mode should therefore be considered separately from position sizing and the maximum loss a trader is prepared to accept.