Stop-loss orders: what guaranteed actually buys
One of these orders is a request you make of the market. The other is a term the broker has agreed to, and it is priced accordingly.
Two orders that share a ticket and little else
On most platforms the distance between a standard stop and a guaranteed one is a tick box. Same level field, same size field, same button. What you tick is not a better instruction, it is a different kind of promise, and the ticket never says so.
Put both in plain words. A standard stop says: when this instrument trades at my level, sell me out at whatever is going. A guaranteed stop says: when it trades there, I am out there, whatever is going. The first depends on the market. The second depends on the broker, who charges for standing behind it.
A standard stop turns into something else the moment it fires
Until it triggers, a stop is a dormant condition attached to a price. Once met, it converts into a market order and queues with every other market order in that second. Everything deciding your fill happens after the trigger, in whatever book exists then. The level you typed chose the moment, never the price.
So a stop filling well below your number has not malfunctioned. It did the only thing it could, which was begin a sale at a time you nominated. People read the figure in the box as a price because it looks like one, and half the platforms selling it call it a stop price. The vocabulary does damage.
Slippage through a stop is simple once you picture the tape rather than the fee line. If the price prints continuously from your level downwards, there is something to sell into nearby and the fill lands close. If it does not print between your level and somewhere far below, no routing arrangement invents a trade that did not happen.
That absence has a short list of causes, all familiar. A market shuts on Friday at one level and opens Monday at another. A central bank speaks at two. A company reports before the bell. Your instruction stays sound throughout, pointed at a range holding no trades.
| Market event | Where a standard stop fills | Where a guaranteed stop fills | Who carries the difference |
| Ordinary session, normal volume | At or within a tick of the level | At the level | Nobody. The two are the same trade |
| Fast move, thin book | Below the level, by an amount quoted nowhere beforehand | At the level | The broker, for the size of the slip |
| Scheduled announcement | Wherever the first price after the release lands | At the level, where cover is offered | The broker, which is why distance rules widen first |
| Weekend or overnight gap | At the reopening price, however far away | At the level | The broker. This row is the whole product |
| Suspension, then a lower reopen | At the reopen, once quoting resumes | Depends on the coverage schedule | Unsettled until you read the terms |
| Account reaches the 50% close-out first | Closed by the account rule, not your level | Closed by the account rule as well | You. The rule does not read order types |
Every row is drawn from product terms rather than from anything recorded on a statement.
The premium you may never pay, and the charge you always do
The premium is usually payable only if the stop is triggered. Tick the box, hold the position, close it yourself in profit, pay nothing. Sit with how odd that is. A policy whose premium falls due when you claim works because most stops are never touched, so one rare event is priced across everybody ticking the box.
It also deletes the moment where a customer weighs certain cost against uncertain benefit, which is where protection products lose the sale. Nothing underhanded happens; the terms say what they say. But a charge surfacing only in a scenario you are not planning for is one most buyers never price.
Guaranteed stops carry a minimum distance from the current price, wider than a standard stop must respect and wider again on volatile instruments or before known events. Some firms withdraw cover entirely around a release. That distance rule is a charge in the units of the instrument, and it applies on the occasions nothing happens as firmly as on the one where it earns its keep.
Price it and the bargain becomes legible. You accept a larger certain loss on trades that go mildly wrong for a fixed loss on the rare one that goes badly wrong. Whether that is worth doing turns on how often each happens to you, a fact about your instrument and your holding period that no broker page contains.
The half of this product nobody can test on your behalf
A difficulty lands on anyone publishing research about stops, including those paying real deposits to do it. A funded-account programme records execution speed and measured slippage, evidence gathered in conditions you can walk into on purpose: a quiet hour, a busy one, a fast few minutes. Those are the conditions in which the two order types behave identically.
Nobody can buy a gap. You cannot schedule the Monday that opens two per cent lower, so no measured comparison across a useful sample of gaps can be made. Premiums, minimum distances and availability windows are verifiable from a live account. The payoff is not. Every account of guaranteed stops, this one included, argues from mechanism where it would most like a measurement.
Your level and the account rule answer to different owners
A stop watches an instrument. The close-out rule watches your equity. When equity falls to 50% of required margin, an FCA-regulated broker must begin closing positions, whatever you attached to the ticket. That threshold holds no opinion about your level and never consults it.
Both rules are written down before you deal, and both are worth checking against a funded account rather than a marketing page, which is the working method at The Investors Centre: it opens and funds live accounts with its own money to test UK trading platforms rather than compiling rankings from providers’ published fee schedules.
The practical use of that beats the trivia. A guaranteed stop converts the worst case on a position into a figure you hold before opening it. Add those figures across everything you carry, set the total against the equity that would take you to the threshold, and the account rule need never get an occasion to fire.
You already own the protection most buyers think they are purchasing
Take the floor as given, because a UK retail account already has one and it was not sold to you. What buyers picture when they reach for a guarantee is usually that floor, and they have it before they pay anything. What the guaranteed stop covers is the band underneath. Between the loss you chose when you set the level and the loss you would take if the balance went, negative balance protection offers nothing, because the balance is where its cap sits. That band is the entire product, and it is narrower than the phrase people reach for.
Ask about the size before you ask about the product
Work out what the largest gap this instrument has delivered would do to your account at the size you deal in. Not an average day. The worst Monday. If the answer is unpleasant but survivable, that is a risk you can carry.
If it would remove a serious part of the balance, a guaranteed stop is one remedy and a smaller position the other. Only one has a price list.
Plain dealing means naming which side holds the information. The firm setting the premium has watched every gap that ran through its book and knows what standing behind a level costs to supply. You are estimating from memory and a chart. That does not make the cover poor value. It puts the work of establishing what you are buying where it least conveniently sits, on the buyer.