Slippage explained: why your order fills at a different price

Slippage is the gap between the price you expected when you sent an order and the price at which it was actually filled. It happens because prices move in the milliseconds between your click and the execution, and because there may not be enough volume available at your price. It can work for you (positive slippage) or against you (negative slippage), and it is a real trading cost even though it never appears on a broker's price list.

What slippage actually is

Every order you send is a request, not a promise. When you press "buy" on EUR/USD at 1.0850, your platform sends that request to the broker, the broker either fills it from its own book or passes it to a liquidity provider, and a fill comes back. If the price at that moment is still 1.0850, you get 1.0850. If the price has moved to 1.0852, you may get 1.0852. Those two pips are slippage.

There are two separate reasons this happens:

• The price moved. Forex prices update many times a second in active periods. Even a fast connection has a delay between what you see and what is executable, and in a fast market the quote you clicked on may already be stale.
• There was not enough volume at your price. A quote comes with a limited amount available. If you want to buy 5 lots and only 2 lots are offered at 1.0850, the rest has to be filled at the next available prices, perhaps 1.0851 and 1.0852. Your average fill is worse than the quote you saw.

The first reason affects everyone. The second mostly affects larger orders, thin markets and exotic pairs, but in a news spike even a small order can find that the liquidity has simply vanished for a moment.

Slippage is measured in pips, like the spread. If you are not yet comfortable converting pips into money, read what a pip is first, because the point of this guide is to turn slippage from an annoyance into a number you can budget for.

Negative and positive slippage

Negative slippage is what everyone notices: you buy higher than you wanted or sell lower than you wanted. Positive slippage is the reverse: the price moved in your favour between the click and the fill, so you bought lower or sold higher than requested.

On a genuinely fair execution model, positive and negative slippage both happen, roughly in proportion to how the market was moving. In a quiet market most orders fill at the requested price, with small slips in both directions. In a fast market you will see larger slips, and they will tend to go against you more often simply because fast markets are usually moving in the direction everyone is trying to trade.

What you should not see is a pattern where every slip goes against you and none goes for you. That is called asymmetric slippage, and it means the execution logic accepts price moves that hurt you and ignores ones that would help you. Regulators in the EU and UK treat it as a conduct issue because it is inconsistent with a broker's duty to act in the client's best interests. We come back to how to check for it later.

Which orders can slip

Whether an order can slip depends on what kind of order it is. The order types guide covers each in detail, but the slippage rules are simple:

• Market orders can slip in either direction. You are asking to trade now at whatever the best available price is.
• Stop orders can slip. A stop, whether it is a stop entry to join a breakout or a stop loss on an open trade, becomes a market order once its trigger price is touched. It then fills at the next available price, which in a fast market can be well past your level.
• Limit orders cannot fill at a worse price than you set. A buy limit at 1.0800 will fill at 1.0800 or lower; a sell limit at 1.0900 at 1.0900 or higher. You can get positive slippage on a limit, but not negative. The trade-off is that a limit might not fill at all.
• Take-profit orders are limit orders, so they fill at your target or better.

The order that slips most painfully for most people is the stop loss, because it triggers precisely when the market is moving hard against you. A 20-pip stop that fills 8 pips late is a 28-pip loss. Position sizing built on the 20-pip figure is then quietly wrong by 40%.

Market execution vs instant execution, and requotes

Brokers handle the "price moved before I filled you" problem in one of two ways, and the MetaTrader platforms label them explicitly.

Market execution means the broker fills your order at the best available price when it arrives, whatever that is. You get a fill nearly every time, but it may differ from the price on your screen. This is the norm for most retail forex accounts today, especially raw-spread and ECN-style accounts.

Instant execution means the broker tries to fill at exactly the requested price. If the price has moved beyond a tolerance you set (the "maximum deviation" in MetaTrader), the order is rejected or you receive a requote: a pop-up offering a new price that you can accept or decline. Requotes protect you from a bad fill, but they also cost you the trade at the moment you wanted it, and in a fast market you can be requoted several times in a row.

Neither model is inherently better. With market execution you accept some slippage in exchange for certainty of a fill. With instant execution you accept missed trades in exchange for certainty of price. What matters is that the rules are applied fairly and the same way in both directions. Frequent requotes in quiet conditions, or requotes that only appear when the price has moved in your favour, are red flags. The guide on ECN, STP and market maker execution explains how execution models relate to these behaviours.

When slippage gets worse

Slippage is not random. It clusters around predictable moments, which is useful, because you can plan around them.

Scheduled economic releases

Around major data such as US non-farm payrolls, CPI or a central-bank rate decision, liquidity providers widen their prices or step back for a few seconds before and after the number. The quote can jump 10, 20 or more pips in one tick. A market or stop order sent into that moment fills wherever the next real price is. The economic calendar guide shows how to see these events coming, and how economic data moves forex explains why the first seconds are so disorderly.

The daily rollover

At 5pm New York time the trading day ends and positions are rolled to the next value date. For a few minutes either side, liquidity is thin and spreads widen sharply, sometimes to several times their normal width. Stops that sit close to the price can be triggered by the wider spread alone, and fills during this window are frequently poor. Our guide to forex market hours and sessions covers the timing, including how it shifts when daylight saving changes in different countries on different dates.

The weekend gap

Retail forex trading stops on Friday evening New York time and resumes on Sunday evening New York time, which is Monday morning in Sydney. Anything that happens over the weekend, an election result, a political announcement, a geopolitical event, is priced in at the reopen. If the first price on Sunday is 60 pips below Friday's close, every stop loss sitting in that 60-pip range is filled at or near the new price, not at its own level. That is a gap, and it is the most extreme form of slippage most traders meet.

Thin pairs and quiet hours

Exotic pairs such as USD/TRY or USD/ZAR, and even some minor crosses, have less liquidity than EUR/USD at the best of times. During the late New York and early Asian hours, liquidity in European pairs thins as well. Orders in these conditions are more likely to walk through several price levels to fill.

Your own order size

A 0.10-lot order will almost always fill in full at the top of the book. A 20-lot order may not. Retail traders rarely trade sizes large enough for this to matter on majors, but on exotics and indices it can.

A worked example of slippage cost

Here is an illustrative example of what slippage does to the numbers. The prices are made up for the example.

Suppose you have a $10,000 account and you risk 1% per trade, $100. You plan a long trade on EUR/USD with a 25-pip stop. On a USD-denominated account one standard lot of EUR/USD is worth $10 per pip, so the position sizing maths gives:

• $100 ÷ (25 pips × $10) = 0.40 lots

Now three things happen:

1. You enter with a market order just after a data release. You wanted 1.0850; you are filled at 1.0853. That is 3 pips of negative slippage, or 3 × $4 = $12 at 0.40 lots ($4 per pip at that size).
2. Your stop is still at 1.0825 (you placed it relative to your intended entry), so your real stop distance is now 28 pips, not 25.
3. The trade goes wrong in a fast market and your stop slips by 4 pips, filling at 1.0821.

Your loss is 1.0853 − 1.0821 = 32 pips × $4 = $128, not the $100 you planned. You risked 1% and lost 1.28%. Do that across a losing streak and the gap between "planned" and "actual" becomes significant.

Now a calmer version. You enter with a limit order at 1.0850, get filled at 1.0850, and the stop fills exactly at 1.0825 during the London session. You lose exactly $100. Same idea, same chart, 28% less damage, just from choosing when and how you executed.

The lesson is not that slippage is unavoidable chaos. It is that slippage has a cost, the cost is concentrated in specific conditions, and your plan should account for it.

How to estimate your own slippage

Most traders have no idea what their real slippage is, because nobody tells them and they never measure it. You can measure it with nothing more than your trade history.

1. For each trade, note the price you intended (the price on screen when you clicked, or the level of your pending order).
2. Note the fill price from your account statement.
3. Record the difference in pips, with a sign: negative when it cost you, positive when it helped.
4. Tag each trade with the conditions: normal session, news, rollover, weekend open.

After 50 or 100 trades you will have a realistic figure. Many traders find that their average slippage in normal conditions is a fraction of a pip, while their average around news is several pips, and that a handful of large slips account for most of the total. Our guide to keeping a trading journal has a template that includes these fields.

If you use MetaTrader, the account history shows the requested price for pending orders and the fill price, which makes stops and limits easy to audit. Market orders are harder, because the platform does not record what you saw when you clicked; a quick screenshot or a manual note is the only reliable way.

How to keep slippage small

You cannot eliminate slippage, but you can control how much of it you are exposed to.

• Use limit orders for entries where you can. If you are happy to buy at 1.0850 but not at 1.0855, a buy limit at 1.0850 enforces that. You will miss some trades. That is the price of price certainty.
• Avoid trading into scheduled releases unless trading the release is your actual strategy. Waiting five or ten minutes for spreads and liquidity to return is usually cheap.
• Do not leave tight stops open over the rollover or the weekend if a few pips of extra slippage would change the outcome. Either widen the stop and reduce size, or close the trade.
• Prefer liquid pairs and liquid hours. EUR/USD during the London and New York overlap fills better than an exotic cross at 11pm.
• Size for the stop you will actually get, not the stop you typed. If your journal shows your stops slip by 2 pips on average, include 2 pips in the stop distance you feed into the position-sizing formula.
• Check the broker's maximum deviation setting if you use instant execution, and set it consciously rather than leaving the default.
• Consider a stop with a fill promise for event risk. Some brokers sell a premium stop that they commit to filling at your exact level, even through a gap. You pay a fee, usually only if it triggers. These are worth understanding if you hold positions over weekends or through major events.

Slippage, execution quality and the broker

How much slippage you get depends partly on the market and partly on your broker.

Under MiFID II, investment firms in the EU, including CySEC-licensed brokers, must take all sufficient steps to obtain the best possible result for clients when executing orders. "Best possible result" is not just price; it also includes costs, speed, likelihood of execution and settlement, size and other relevant factors. Firms must have an order execution policy and make it available to clients. The UK applies equivalent rules under the FCA. This does not mean a regulated broker will never slip you. It means the firm must have a documented, consistent process and must not structure execution against you.

Practical signs of decent execution:

• Positive slippage shows up in your history, not just negative.
• Fills in normal conditions are usually at, or within a fraction of a pip of, the requested price.
• Requotes are rare outside of news.
• Stops trigger on prices that are visible on other feeds or charting platforms around the same time.

Practical signs of poor execution:

• Every slip goes against you.
• Stops are hit by spikes that appear on your broker's chart and nowhere else.
• Execution is noticeably worse after you start winning, or on larger sizes, with no market reason.
• The order execution policy is hard to find or vague about slippage.

If you see the second list, start by asking the broker for a written explanation of specific fills. A regulated firm should answer. If it does not, the regulator's complaint process exists for exactly this. Our guide on how forex brokers make money explains why market-maker models create the incentives that make these checks worth doing, and how to choose a forex broker puts execution in the wider checklist.

Gaps and extreme events

The most severe slippage happens when the market does not trade through prices at all but jumps over them.

The best-known example in forex is 15 January 2015, when the Swiss National Bank abandoned its 1.20 floor under EUR/CHF without warning. The pair fell from around 1.20 to well below 1.00 within minutes, with almost no trading in between. Stop losses were filled hundreds of pips beyond their levels. Many retail accounts ended with negative balances, and some brokers suffered losses large enough to put them out of business; Alpari's UK arm went into administration days later.

That event is one of the reasons the 2018 ESMA measures made negative balance protection mandatory for retail CFD clients in the EU, so that a retail client cannot lose more than the money in their account. It is also the clearest illustration of why a stop loss is a risk-reduction tool and not a ceiling on your loss. The guide to ESMA leverage limits and negative balance protection covers those rules in full, and the margin call and stop-out guide explains what happens to an account when a gap blows through its margin.

You do not need to fear events like that every day. You need to size positions so that one of them would hurt rather than end your trading.

Common mistakes

• Assuming the stop is the maximum loss. It is the price at which a market order is triggered. In normal conditions that is almost the same thing. In a fast market it is not.
• Blaming every slip on the broker. Some slippage is simply the market. Measure before you accuse.
• Ignoring positive slippage. If you never check for it, you cannot notice if it is missing.
• Placing stops a pip or two from the price before a release. You are paying the spread and the slippage to be stopped out by noise.
• Trading exotics with major-pair expectations. Wider spreads and thinner books mean larger and more frequent slips. Budget for it.
• Leaving it out of cost comparisons. A broker with a 0.1-pip tighter spread but consistently worse fills is not cheaper. The spreads and commissions guide shows how to calculate the all-in cost; slippage belongs alongside it.

Leverage makes all of this matter more. Slippage is measured on the full position, so on a heavily leveraged account a few pips of slip is a much larger share of your capital. The leverage and margin guide explains why, and our risk warning sets out the wider picture: most retail CFD accounts lose money.

Frequently asked questions

Is slippage a sign my broker is cheating me?

Not by itself. Slippage is a normal part of trading in fast or thin markets, and every broker has it. It becomes a concern when it is consistently one-sided, when it is large in quiet conditions, or when stops are triggered by prices that did not appear elsewhere. Measure your fills for a few weeks before drawing a conclusion.

Can a limit order slip?

A limit order cannot be filled at a worse price than your limit. It can be filled at a better price, which is positive slippage, or not filled at all if the market never reaches your level or only touches it with insufficient volume. Take-profit orders work the same way.

Why did my stop loss fill so far from where I set it?

Because a stop loss becomes a market order once triggered. If the price jumped past your level, after a data release, at the weekend open or in a thin market, the order filled at the next available price. The only way to avoid that is a stop that the broker commits to filling at your exact level, which usually carries a premium.

What is a requote?

A requote is the broker's response when you request a specific price under instant execution and that price is no longer available. The platform offers a new price that you can accept or reject. Requotes are more common around news and on accounts that use instant execution rather than market execution.

How much slippage is normal?

On a major pair in liquid hours, most fills should be at the requested price or within a fraction of a pip. Around big news, several pips is common and more is possible. The honest answer is that it varies by pair, time, size and broker, which is why measuring your own fills is more useful than any general figure.

Does slippage affect demo accounts?

Usually much less than live accounts. Many demo servers fill at the quoted price with no slippage at all, which is one reason live results often fall short of demo results. Treat demo fills as optimistic and budget for real-world slippage before you trade live.