What it means
An ordinary market order says "trade now at whatever the price is". A conditional order says "trade only if something happens first", and until that trigger occurs the order sits dormant in the broker's system without affecting the market.
The common types are worth knowing by name. A stop order triggers a market order once a price is touched, a limit order executes only at a stated price or better, a stop-limit combines the two, and a one-cancels-other pairs a profit target with a stop so that filling one automatically cancels the other.
The business reason for using them is discipline. Losses are usually made worse by hesitation, and a stop order placed at the moment of purchase, when the investor is calm, enforces the exit level that seemed sensible before any money was at stake.
The mechanics have a trap that people learn expensively. A stop order guarantees that an order will be sent, not the price it fills at, so in a fast-moving or gapping market the actual execution can be well below the trigger, which is the gap between the theoretical and the realised loss.
Conditional orders extend well beyond stock trading. Treasury teams place conditional foreign exchange orders that execute if a rate is reached overnight, and commodity buyers use them to lock in input costs without staffing a night desk.
In practice
Real-world examples.
Example
A company treasurer needs to buy 2,000,000 euros within the month and places a conditional order to execute if the rate reaches a level that fits the budgeted exchange rate. The order fills at 3am local time while nobody is at a desk.
Example
A private investor holding a stock that has doubled sets a one-cancels-other order: sell at a 20% higher target, or sell if the price falls 12%. Whichever triggers first cancels the other, so the position is managed without daily monitoring.
Example
A fuel buyer for a haulage firm places a conditional purchase order for three months of diesel that activates only if the wholesale price drops below a stated threshold. When it does, the hedge is placed automatically and the budget is protected.
Formula
Calculation
Loss avoided by a stop order = (loss without the stop) - (loss with the stop), where loss with the stop = (purchase price - actual fill price) x number of shares.
An investor buys 5,000 shares at $50.00, a position worth 5,000 x $50.00 = $250,000. She places a stop-loss order at $42.00 at the same time.
The share price falls through $42.00 on bad results and the stop triggers. Because the market is moving quickly the order actually fills at $41.80.
Proceeds: 5,000 x $41.80 = $209,000. Realised loss: $250,000 - $209,000 = $41,000.
The share continues falling and settles at $35.00 over the following week. Had she held on, the position would be worth 5,000 x $35.00 = $175,000, an unrealised loss of $250,000 - $175,000 = $75,000.
Loss avoided: $75,000 - $41,000 = $34,000. Note also the $1,000 of slippage, being 5,000 x ($42.00 - $41.80), which is the cost of the stop triggering a market order rather than a guaranteed price.Case study
Seen in the real world.
The following is an illustrative and fictional scenario. Larkspur Capital, an invented boutique investment firm, ran a concentrated portfolio of 22 holdings and had a written rule that no position should be allowed to lose more than 15% of its entry value.
The rule existed on paper, but in practice the portfolio manager found reasons to wait whenever a holding fell, and in this fictional account two positions ended down 46% and 52% before being cut. The firm's risk committee concluded the problem was not the rule but the absence of any mechanism to enforce it.
Larkspur changed its process so that every new position had a stop order entered at the same moment as the buy, at the 15% level, with any removal requiring written sign-off from a second partner. In this illustrative outcome the discipline cost the fund a handful of positions that later recovered, but the committee judged that acceptable against two avoidable losses that had each been large enough to shape a full year of returns.
Watch out
Common mistakes.
- Believing a stop order guarantees the exit price. It guarantees only that an order will be sent once the trigger is touched, and the fill can be materially worse in a gapping market.
- Setting the trigger inside normal daily volatility. A stop placed 3% below the price on a share that routinely swings 4% a day will be triggered by noise rather than by any real change.
- Forgetting that conditional orders expire. Day orders die at the close, so an order intended as a standing protection must be entered as good-till-cancelled and checked periodically.
Questions
People also ask.
What is the difference between a stop order and a limit order?
A stop triggers a trade once a price is reached and then takes whatever the market offers, while a limit will only execute at your stated price or better and may never fill at all.
Do conditional orders work outside market hours?
The trigger is generally only monitored during the hours the relevant market trades, so a price that gaps overnight can open well past your level before the order becomes live.
Can conditional orders be used for buying as well as selling?
Yes. Buy stops are used to enter a position once a price breaks upward through a level, and buy limits are used to accumulate only at or below a target price.
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