Stop Loss: What It Is, Where to Place It and Why It Can Slip
A stop loss is an order that closes your trade automatically if price reaches a level you set, to limit the loss. Used well, it is not placed by how much money you want to lose but where your analysis stops making sense; the money at risk is then controlled with the position size.
Where to place it
- By structure: on a buy, below the last relevant low or support; on a sell, above the last relevant high.
- By volatility: at a distance in line with how much the asset normally moves (say, 1.5 times its average daily range). A stop tighter than normal market noise gets hit for no reason.
- Never by money alone: “my stop is at $50 because that’s what I want to lose” usually puts it somewhere with no logic.
The stop sets the size, not the other way round
With $100 at risk on EUR/USD ($10 per pip per lot): a 20-pip stop allows 0.50 lots; a 50-pip stop, 0.20 lots. Either way, if the stop is hit you lose $100. That is how you put the stop where it belongs without risking more. Lot size calculator · risk/reward.
Why you sometimes lose more than planned
- Slippage: the stop fills at the next available price. In very volatile moments, such as the jobs report or a rate decision, that can be several pips worse.
- Gaps: if the market opens on Sunday night far from Friday’s close, the stop fills at the open, not at your level.
- Spread: on a short the stop triggers on the ask price; if the spread widens it can fire before your chart shows it.
Some brokers outside the US offer guaranteed stops, filled at your price no matter what, for a fee if triggered.
Trailing stops and break-even
When the trade moves your way you can move the stop to your entry (break-even) or use a trailing stop that follows at a fixed distance. They protect gains, but set too close they will close good trades on normal pullbacks.
Trading with a prop firm? The stop matters even more because of its daily loss limit: how prop firms work.
Information only, not investment advice. Leveraged trading can lose you more than you put in.
Frequently asked questions
Where should I place my stop loss?
Where your idea stops being valid: below a relevant low on a buy, above a relevant high on a sell, with some room for volatility. Then size the trade so that stop risks what you decided.
Does a stop loss guarantee the price?
No. A regular stop becomes a market order when hit and can fill worse if price jumps (news, the weekly open). Only a guaranteed stop, which some brokers offer for a fee, locks the price.
What is a trailing stop?
A stop that follows price at a fixed distance as the trade moves your way, and never moves back. It protects profits but can take you out on a normal pullback.
Is it better to close trades by hand without a stop?
For most traders, no: without a stop, a news release or a lost connection can turn a small loss into a big one. Prop firms also close the account once the daily limit is breached.