A stop-loss is the order that closes a losing trade before it becomes a disaster. It is the most important habit in trading — and the one beginners most often skip, move, or remove. Here's how to use it properly.
What a stop-loss does
A stop-loss automatically exits your position when price reaches a level that proves your idea wrong. It converts an open-ended risk ("how low could this go?") into a known, fixed loss you accepted before entering.
Where to place it
Not at a random distance — at the price that invalidates your reason for the trade:
- Just beyond a support or resistance level you expected to hold.
- Beyond a swing high/low that, if broken, means the structure has changed.
- Far enough to survive normal noise, close enough to keep the loss small.
The stop comes first. Its distance then drives your position size — not the other way around.
The cardinal sins
- No stop at all — one bad trade can erase weeks of gains.
- Moving the stop wider to avoid being stopped out — this turns a small planned loss into a large unplanned one. The most expensive habit in trading.
- Stops too tight — placed inside the noise, they get clipped before the move happens.
A note on slippage
In fast markets or gaps, a stop may fill slightly past your level. It's still vastly better than no protection. For overnight and weekend gap risk — common in crypto — size smaller.
You will be wrong often. The stop-loss is what makes being wrong survivable.
Education only — not financial advice.