Maintenance margin is the minimum collateral level that must be maintained to keep a leveraged or derivative position open.

After a position is opened, its value changes with the market. Losses reduce the available collateral. If collateral reaches the maintenance margin threshold, the exchange may initiate liquidation.

Initial margin vs. maintenance margin

Initial margin is the requirement for opening a position. Maintenance margin is the threshold that must remain available after the position is open.

Maintenance margin is generally lower than initial margin. This allows a position to remain open after entry while the trader still has sufficient collateral to cover potential losses.

Exact values and calculation methods depend on the exchange, instrument, position size, and margin mode.