Stop Loss: The Order That Defines Your Risk
Macro Glossary, Orders and Risk
By Ken Chigbo, macro trader and founder of KenMacro, 18+ years in markets.
Updated 2026-05-20
The desk’s answer
A stop loss is an order that closes an open position when price reaches a specified adverse level. It becomes a market order once the stop level is touched, filling at the prevailing market price (which can include slippage). The stop loss converts an open position from unbounded risk to defined risk: the trader knows the maximum loss before entering the trade. Position sizing is calculated against the stop distance, with the loss at the stop equal to the chosen risk percentage of account balance, typically 0.5 to 2 percent per trade.
Defined term, Stop loss
A stop loss is a resting order that closes an open position when price reaches a specified adverse level, capping the realised loss on the trade. It becomes a market order when the stop level is touched, fills at the prevailing market price, and is the primary mechanism for converting an unbounded risk position into a defined-risk one with a maximum loss.
How stop loss orders work mechanically
A stop loss is a conditional order resting on the broker’s server. For a long position, the stop sits below entry; for a short, above entry. When the bid price (for longs) or ask price (for shorts) reaches the stop level, the resting order is triggered and becomes a market order, which fills against available liquidity. The fill price is normally close to the stop level but can be worse in fast markets or on gaps (negative slippage). Some brokers offer Guaranteed Stop Loss Orders (GSLO) that fill at the requested level regardless of market conditions, in exchange for a premium charged on the position.
Stop placement: structure vs ATR vs fixed
Three common stop-placement methods. Structural: the stop sits beyond a key level (prior swing high or low, weekly extreme, supply or demand zone) that, if breached, invalidates the trade thesis. This is the desk’s preferred method because the stop is informationally meaningful. ATR-based: the stop sits at 1.5x or 2x the recent ATR, adapting to volatility but ignoring structure. Fixed-pip: the stop sits at an arbitrary 20 or 50 pips, which works in steady regimes and fails in volatility transitions. Stop placement determines position size, so the structural method also forces the trader to size correctly for the trade rather than for the size they want to trade.
Why stop loss orders matter for survival
Without a stop loss, a single oversized losing trade can consume a meaningful fraction of an account or, in extreme cases, the entire balance. With a 1-percent-per-trade stop, the trader can lose 20 consecutive trades and retain 82 percent of starting capital (compounded), enough to keep a viable strategy alive. The stop is therefore the mechanism that separates the population of traders who survive their first bad streak from the population that does not. The discipline is not finding the perfect stop placement; it is having a stop on every trade and sizing the position against it.
Frequently asked
What is a stop loss?
A resting order that closes an open position when price reaches a specified adverse level, capping the realised loss on the trade. It becomes a market order when triggered, fills at the prevailing market price, and is the primary mechanism for defining maximum loss before entering a trade.
How far should a stop loss be from entry?
Far enough to sit beyond the key structural level that would invalidate the trade thesis, or at 1.5x to 2x the recent ATR. Position size is then calculated so the loss at the stop equals the chosen risk percentage of account balance, typically 0.5 to 2 percent per trade.
Can a stop loss fill at a worse price than requested?
Yes. A stop loss becomes a market order when triggered, so it fills at available liquidity. In fast markets or on gaps the fill can be materially worse than the stop level. Guaranteed Stop Loss Orders, offered by some brokers for a premium, fill at the requested price regardless of conditions.
What this means at the desk
Every trade has a stop. The size is decided by the stop, not the other way round.
Read next from the desk
Educational glossary entry only,
From the desk
Knowing the term is step one. The next question is always which broker actually serves you well. The desk audits eight brokers on regulation by entity, true cost, and honest fit, with the regulatory caveats the comparison sites bury.
not financial advice and not a trade signal. The desk teaches a reading framework, never entries, targets or recommendations. Trading forex, indices and leveraged products carries significant risk and may not be suitable for all traders. Some broker links on this site are commercial partnerships and KenMacro may receive compensation, which does not change the editorial view. Only trade with capital you can afford to lose.
From the desk, free
Get the macro framework the desk actually trades
The same regime-first framework behind every call on this site, plus the weekly macro brief. Free. No spam, unsubscribe anytime.
Continue reading
From the desk
Where this gets traded
Reading the macro driver is half of it. The other half is an account that holds execution when the driver actually moves the tape. See the KenMacro desk guide to the best brokers for macro traders.
Read the desk guide →