What Is Leverage in Trading? How It Works and What It Costs

A ratio of 1:30 means each dollar of margin supports thirty dollars of exposure. Retail leverage is capped in many jurisdictions — commonly 1:30 for major FX in the EU and UK — while prop firms typically offer higher ratios on simulated accounts.

Required margin = position notional ÷ leverage ratio. A $100,000 position at 1:100 requires $1,000 of margin; the same position at 1:500 requires $200. The exposure is identical in both cases.

This is the point that matters. Two traders both buy one lot with a 20-point stop. One has 1:30 leverage, the other 1:500. Both lose the same amount if stopped out, because loss is determined by position size and stop distance, not by the leverage ratio.

What higher leverage changes is the maximum position you are permitted to open. It expands the ceiling on how much damage you can do, which is why it feels dangerous — but the danger comes from choosing to use that ceiling, not from the ratio itself.

Used margin is the capital locked up by open positions; free margin is what remains available. Margin level is equity divided by used margin, expressed as a percentage.

When margin level falls below a threshold, positions are liquidated automatically. On a funded account this is rarely the binding constraint — the drawdown limit is almost always reached first, so the drawdown rule is the one to manage against.

Prop firms provide leverage on simulated capital, which is why a $10,000 challenge can carry meaningful position sizes. The account rules, not margin availability, define the real constraint.

The practical implication is that available leverage should be treated as irrelevant when planning a trade. Size from your risk percentage and your stop distance; if the resulting position needs more margin than is free, the trade is too large regardless of what the ratio permits.