What Slippage Really Costs You (and How to Measure It)
Understanding what slippage really costs you is one of the most overlooked parts of trading, yet it can quietly drain more from your account than spreads or commissions combined. This guide shows you exactly what slippage is, where it hides, and how to measure it on your own trades so you can stop guessing and start managing it.
What Slippage Actually Is
Slippage is the difference between the price you requested when you placed an order and the price you actually got filled at. It happens because markets move between the moment you click "buy" or "sell" and the moment your broker's system executes the order.
A few basics worth knowing:
- Negative slippage means you got a worse price than expected (bought higher, sold lower).
- Positive slippage means you got a better price than expected.
- Slippage can occur on market orders, stop orders, and sometimes limit orders that fill partially.
- It's most common during high volatility, low liquidity, or fast-moving news events.
It's not a sign something is broken — it's a normal feature of how electronic markets fill orders. The problem is that many traders never actually measure it, so they have no idea whether it's a minor nuisance or a serious drag on their results.
Why Slippage Costs More Than Traders Think
A single slipped pip feels trivial. The real cost shows up in volume and frequency:
- It compounds with position size. A 1-pip slip on a 1-lot EUR/USD trade is roughly £7–10 depending on the exchange rate; on 10 lots, that's £70–100 — per trade.
- It stacks with every other cost. Spread, commission, swap, and slippage all come out of the same pot. Slippage is just the one most traders never add up.
- It clusters around news. Traders who trade economic releases often see their worst slippage exactly when they can least afford it — during the exact moves they were trying to catch.
- It's asymmetric in practice. While slippage can go either way, many retail traders report more frequent negative slips than positive ones during volatile windows, simply because liquidity thins out as price gaps.
None of this means slippage makes trading unprofitable — it means it needs to be priced in like any other cost, not treated as bad luck.
How to Measure Your Own Slippage
You don't need special software to start measuring slippage — a simple log will do. For every trade, record:
1. Requested price (the price shown when you clicked to open/close). 2. Filled price (the actual execution price shown on your confirmation or statement). 3. Order type (market, stop, limit). 4. Time of day and whether news was scheduled. 5. Pip difference between requested and filled price. 6. Money value of that difference, based on your position size.
After 20–30 trades, total the pip and money columns. You'll typically see:
| Metric | What it tells you | |---|---| | Average slippage (pips) | Your typical execution gap per trade | | Worst single slip | Your tail risk during volatile moments | | % of trades with negative slippage | How often execution works against you | | Total monthly cost | The real pounds-and-pence impact |
Once you have real numbers, run them through PipTax's [cost impact](/cost-impact.html) and [audit](/audit.html) tools to see how slippage stacks up against spread and commission over a realistic month of trading.
Where Slippage Tends to Be Worst
Some conditions reliably increase your exposure:
- Scheduled news releases (NFP, CPI, central bank decisions) — liquidity thins just before the print and floods back after.
- Market open/close transitions, especially the illiquid hour between the New York close and Sydney open.
- Exotic and minor pairs with naturally wider spreads and fewer liquidity providers.
- Large position sizes relative to available liquidity at the best price.
- Slow or distant server connections — if your trading platform sits far from your broker's server, added latency gives price more time to move before your order arrives.
If you consistently trade during any of these conditions, your measured slippage will likely be higher than someone trading liquid majors during London/New York overlap with a nearby server.
Execution Choices That Reduce Slippage
You can't eliminate slippage on market orders, but you can meaningfully reduce it:
- Use limit orders where your strategy allows. You either get your price or better, or you don't get filled — no negative slippage, at the cost of potentially missing trades.
- Avoid trading the first few seconds after major news unless your strategy specifically accounts for it.
- Pick a server location close to your broker's infrastructure — both Pepperstone and IG publish details on their server setups, and checking latency between your location and theirs is worth five minutes of research.
- Compare account types. Raw/ECN-style accounts route orders differently to standard accounts and may execute differently in fast markets — but don't assume one is automatically better without checking.
- Trade smaller size relative to market depth during known thin-liquidity windows.
None of these guarantee zero slippage, but together they shrink your average exposure meaningfully over hundreds of trades.
Checking a Broker's Execution Before You Commit
Before assuming a broker is the problem — or the solution — do the legwork:
- Read the broker's execution policy (most FCA-regulated brokers publish one).
- Check whether they report execution statistics such as average fill speed or requote rates.
- Test with a demo or small live account first, logging slippage the same way described above.
- Compare your findings against PipTax's [broker comparison pages](/brokers/index.html) and see how methodology affects what's being compared — explained fully on our [methodology page](/methodology.html).
Execution quality varies by broker, account type, and even time of day with the same broker — so a single bad fill doesn't prove much. A logged sample over weeks does.
Conclusion: Make Slippage a Known Cost, Not a Mystery
What slippage really costs you is only a mystery if you never measure it. Once you log requested versus filled prices for a few dozen trades, you turn a vague frustration into a concrete, manageable number — one you can reduce with order type choices, timing, and broker selection. Pair your own slippage log with PipTax's [cost audit tool](/audit.html) to see the full picture of spread, commission, and slippage together, and visit our [trading school](/school/index.html) for more on building execution discipline into your routine. Trading always carries risk, and no amount of measurement removes that — but it does stop slippage from being an invisible cost you're paying without knowing it.
Key takeaways
- Slippage is the difference between your requested price and your actual fill — it can work for or against you, but on average it tends to cost active traders money.
- Market orders during news releases, low-liquidity hours, or on wide-spread pairs are where slippage bites hardest.
- You can measure your own slippage by logging requested vs filled price on every trade, in pips and in money terms.
- Execution type (market vs limit), account type (standard vs ECN/raw), and broker server location all affect how much slippage you absorb.
- A few pence per trade in slippage compounds fast — run the numbers through a cost tool rather than guessing.
- You can reduce slippage with limit orders, avoiding scheduled news spikes, and checking a broker's execution stats before committing capital.
Frequently asked questions
- Is slippage always bad for traders?
- No. Slippage is simply the gap between the price you requested and the price you got — it can be negative (worse fill) or positive (better fill). In fast markets both happen, but studies of retail execution generally show negative slippage occurs more often around news and thin liquidity, which is why it's worth tracking rather than ignoring.
- Does slippage only happen with market orders?
- Mostly, yes. Market orders accept the next available price, so they're exposed to slippage. Limit orders either fill at your price or better, or don't fill at all — so they remove slippage risk but introduce the risk of missing the trade entirely.
- How much slippage is 'normal'?
- There's no universal number — it depends on the pair, time of day, account type, and broker's liquidity providers. Rather than relying on a rule of thumb, log your own fills for a few weeks and compare the average to what PipTax's cost tool shows for similar conditions.
- Can I eliminate slippage completely?
- Not entirely if you use market orders, but you can reduce it significantly by avoiding high-impact news windows, trading liquid major pairs, choosing a broker with solid execution, and using limit or stop-limit orders where your strategy allows.
- Do ECN or raw-spread accounts have less slippage than standard accounts?
- Often they offer faster, more direct execution because orders are routed to liquidity providers rather than a dealing desk, which can reduce slippage — but this varies by broker and isn't guaranteed. Check a broker's execution policy and real trader reports rather than assuming.
- How do I measure slippage on my own trades?
- Record your requested price and your filled price for every order, in a spreadsheet or trade journal. Subtract one from the other to get slippage in pips, convert to money using your position size, then total it monthly to see the real cost to your account.