Risk and execution · 4 / 5
Choose between stop-market and stop-limit orders
A stop has two distinct jobs: detect a condition and submit an order. The trigger price answers when to act. The resulting order type determines which executions are permitted. Confusing these jobs can leave a losing position open precisely when you expect protection.
Athenum7 minUpdated:
The trigger is not the fill price
A stop-market instruction typically submits a market order once its trigger condition is reached. It prioritises execution over a chosen fill price, but available liquidity and venue protections still matter. Some platforms implement market orders as protected immediate-or-cancel limits; an unfilled portion can be cancelled if it falls outside the permitted price range.
A stop-limit instruction submits a limit order. For an exit sell, the limit is the minimum acceptable sale price. If the market gaps below that limit, the order may remain unfilled. Moving the limit farther from the trigger gives it more execution room, while also allowing a worse fill. Neither order type can eliminate gap risk.
Check position semantics as well as price
Reduce-only is intended to prevent an exit from increasing or reversing exposure. It does not guarantee a fill. Position mode, remaining quantity, other exits and exchange restrictions can affect whether an order is accepted or adjusted. Review the actual order status after submission rather than treating a button click as confirmation.
Also check the trigger feed. Last price, mark price and index price can briefly disagree. A stop watching last price may not activate before a mark-price liquidation condition. During a fast market, the relevant question is the order of events on the platform, not whether a candle eventually crossed your drawn line.
The market jumps through both levels
Consider a hypothetical long of 2 units from 100. You set a sell trigger at 98 and a stop-limit price of 97.80. The next executable bid is 97.50, with at least 2 units available and no other changes. A stop-market order can sell there if venue protections permit; a sell limit at 97.80 cannot accept that bid.
The market execution loses (100 − 97.50) × 2 = 5 before fees, compared with a planned price loss of 4 at the trigger. The stop-limit has no realised exit P&L yet because the position is still open. It is misleading to record its loss as zero. If price continues to 95, its unrealised price loss becomes 10 while waiting for a permitted execution.
| Instruction | Result at 97.50 | Exposure afterward |
|---|---|---|
| Stop-market; protection permits | Sell 2 at 97.50 | Flat; 5 price loss |
| Stop-limit at 97.80 | No permitted fill | Still long 2 |
| Partially filled exit | Only available quantity closes | Remaining quantity still at risk |
- 1Trigger condition
- 2Order accepted
- 3Fills / cancellation
- 4Position checked
The remaining quantity is easy to overlook
Suppose only 1.2 of the 2 units fills before an exchange protection cancels the rest. The initial order was valid, but 0.8 units remain exposed. A robust process reconciles fills, remaining position and other pending exits. It also defines what to do if the data connection fails. Repeatedly submitting blind exit orders can create a second problem instead of resolving the first.
Before acting
- Identify the trigger feed and the order submitted after activation.
- Read the venue's market-order protection and partial-fill rules.
- Check reduce-only, position mode, size and minimum requirements.
- Reconcile the final position with executions, including cancelled remainders.
Check your understanding
An exit for 2 units fills 1.2 at 97.50 and the remainder is cancelled. How much is still open, and why is the trigger insufficient evidence of closure?
Show the explained answer
0.8 units remain open. The trigger only activated the instruction; it did not ensure full execution. The next action must follow the predefined contingency for the remaining position and current liquidity, with the venue's actual order status checked first.