Cross margin and isolated margin are two ways to assign collateral to perp positions. The difference is simple, but it changes how losses spread through your account.
Choosing the wrong margin mode can make a trade riskier than you intended.
What isolated margin means
Isolated margin limits a position to the collateral assigned to that position. If the trade goes badly, the damage is more contained. You can usually add more margin to the position if you want to move liquidation farther away.
Many beginners prefer isolated margin because it makes the risk boundary easier to see.
What cross margin means
Cross margin uses available account equity to support positions. If one position loses money, the account can use spare collateral to keep it open longer. This can reduce the chance of liquidation on one position, but it can also expose more of your account to that position.
Cross margin can be useful for experienced traders managing a portfolio, but it requires more discipline.
The main tradeoff
Isolated margin gives cleaner containment. Cross margin gives more flexibility. Neither is automatically safer. A tiny isolated position can be safer than a huge cross-margin position, and a careful cross-margin portfolio can be safer than multiple reckless isolated trades.
Questions to ask before choosing
- Do I want this position's losses capped to a specific amount?
- Am I comfortable with other account collateral supporting this trade?
- Do I have multiple positions that could lose at the same time?
- Have I checked how the liquidation price changes in this mode?
If you are not sure, slow down. Margin mode is not a cosmetic setting. It changes the shape of your downside.
Risk note: Cross margin can put more account equity at risk than expected. This article is educational content, not financial advice.