Margin

Margin is the collateral a trader deposits to open and maintain a leveraged position. It is not a fee — it is your own capital held by the exchange as a buffer against losses, and it is what you lose if the trade goes far enough against you.

For example, opening a $10,000 BTC position at 10x leverage requires about $1,000 of initial margin. As the position loses value, your margin absorbs the loss; if it falls below the exchange's maintenance margin requirement, the position is liquidated. Exchanges distinguish initial margin (needed to open) from maintenance margin (the minimum to stay open).

Most platforms offer two modes. Isolated margin walls off a fixed amount per position, capping the loss to that allocation. Cross margin lets your whole account balance back all positions, which makes liquidation less likely on any single trade but puts the entire balance at risk if things go badly. A common misconception is that margin trading is just "trading with extra money"; the borrowed portion must effectively be repaid through the position's settlement, and interest or funding costs accrue while the position is open.