How to set a stop loss that actually works
6 min read
Most people set a stop loss at a round number — 8% below entry, say — and then get stopped out by ordinary noise before the trade has a chance to work. The stop was not wrong because it was too tight. It was wrong because it was placed somewhere the stock had no reason to respect.
Place the stop where the idea is wrong
A stop loss should sit just beyond the level that would prove your reason for the trade was mistaken. If you bought a breakout above a range, the idea fails when price falls back inside that range and stays there. That is where the stop belongs — a little below the range, not a fixed percentage away from your fill.
This flips the usual order of operations. You choose the stop from the chart first, and then work out how many shares to buy, rather than choosing a size and hoping a percentage stop fits.
Let volatility set the distance
A stock that routinely moves 2% a day and one that moves 9% a day cannot use the same stop distance. The standard way to normalise this is average true range (ATR), which measures typical daily range.
A stop placed inside one ATR of the entry will be hit by ordinary movement most of the time. Placing it beyond the relevant level and outside about 1.5 ATR gives the trade room to breathe without abandoning the plan.
Position size is the actual risk control
Once the stop level is fixed, risk is a matter of arithmetic. Decide the maximum you are willing to lose on the trade — commonly a small fixed percentage of the account — then divide that by the distance from entry to stop to get the share count.
- Risk per trade: pick a fixed figure and keep it constant across trades.
- Stop distance: entry price minus stop price, in dollars per share.
- Shares: risk per trade divided by stop distance.
- A wider stop is not riskier — it just means fewer shares.
Moving a stop, and when not to
Raising a stop as a trade works is reasonable: once price has cleared a new level, that level becomes the new place where the idea would be wrong. Trailing behind structure — recent swing lows, a moving average the stock has respected — is more durable than trailing a fixed percentage.
Lowering a stop is almost never reasonable. It converts a defined, planned loss into an open-ended one, which is the single most common way small losses become account-damaging ones.
Where the levels in our alerts come from
Every alert we send carries three levels: breakout, give up and stretch. The give-up level is the stop in this sense — the price at which the setup we flagged is no longer valid. It is derived from the structure of the setup, not from a fixed percentage, which is why it differs from stock to stock.
Common questions
Should a stop be a market order or a limit order?
A stop-market order will fill but can slip badly on a gap. A stop-limit will not slip but can miss entirely in a fast move. For swing trades, stop-market is usually the more honest choice.
Should stops be visible in the market or mental?
Resting stops get filled during volatility spikes; mental stops rely on you executing under pressure, which people frequently do not. Resting stops placed at a sensible level are the safer default.
How much should you risk per trade?
That is a personal decision, but keeping it small and constant matters more than the exact figure. A consistent small risk survives a run of losses; a variable large one does not.
More guides
A short squeeze in plain English: why a stock can rip higher when the people betting against it are forced to buy back.
What the 0–100 squeeze score measures, what the breakout, give-up and stretch levels mean, and when a setup is actually actionable.
The signs that selling is exhausted, the difference between a base and a falling knife, and how to wait for confirmation instead of guessing.
Note: educational content only, not investment advice. Only invest money you can afford to lose.