On January 15, 2015 at 10:30, the Swiss National Bank (SNB) dropped the 1.20 franc-per-euro floor it had defended for more than three years. EUR/CHF fell toward 0.85 within minutes. Stops placed just below 1.20 were not filled at their price, but wherever a buyer reappeared, often hundreds of pips lower. That day sums up a simple truth: a stop is an order, not a price guarantee.
Picture the "safest" position of your career. A central bank has announced it will buy unlimited euros to keep EUR/CHF from going below 1.20. It has done so since 2011. Three days earlier, its vice-chairman again called the floor the cornerstone of its policy. You buy at 1.2010, stop at 1.1950. Risk: 60 pips. That morning, your actual loss is counted in thousands of pips.
What was the SNB floor?
On September 6, 2011, in the middle of the euro crisis, the Swiss franc was appreciating so fast it threatened the Swiss economy. The SNB set a minimum exchange rate: 1 euro would be worth at least 1.20 francs. To defend it, it bought euros, with francs it created, whenever the rate approached the threshold.
For more than three years, the floor held. For many traders, 1.20 became a risk-free level: buy near the floor with a stop just below.
What happened on January 15, 2015?
On January 12, 2015, SNB vice-chairman Jean-Pierre Danthine publicly reaffirmed the floor as the cornerstone of monetary policy. On January 15, at 10:30 Zurich time, the SNB announced it was abandoning it.
The one buyer holding the level vanished. Sellers were plentiful: every stop below 1.20 triggered at once. EUR/CHF dropped toward 0.85 within minutes (the exact level varies by source and platform), before climbing back above 1.00 the same day.
A move of roughly 30% in a major currency pair, in minutes.
Why weren't stops filled at their price?
Because a regular stop loss is a conditional market order. When price touches your level, it becomes a sell order at the best available price. If there is no buyer at 1.1950, or 1.1900, or 1.1000, the order is filled lower, wherever a buyer finally takes the other side.
That is slippage: the gap between the price you asked for and the price you got. On a normal day, it is a fraction of a pip. On January 15, 2015, it was hundreds of pips, sometimes more.
What were the consequences?
For traders, losses far beyond the planned risk. With leverage, many accounts went negative: clients owed money to their broker.
For brokers, the hit was direct. FXCM reported about $225 million in negative client balances. Alpari UK went into administration a few days later.
In Europe, this episode is among those that led to ESMA's 2018 measures on CFDs for retail clients, including negative balance protection and leverage limits.
What does a stop filled 10 times further away cost?
Example (example figures): a $10,000 account, 1% planned risk ($100), 50-pip stop. Size is set so that 50 pips cost $100.
| Stop fill | Actual distance | Loss | % of account |
|---|---|---|---|
| At the planned price | 50 pips | $100 | 1% |
| Moderate slippage | 80 pips | $160 | 1.6% |
| News gap | 200 pips | $400 | 4% |
| Extreme gap | 500 pips | $1,000 | 10% |
Your real risk is not "the stop distance" but "the distance to where you actually get filled". On most days, the two are the same. In a shock, they have nothing in common.
Log the actual exit price of every trade →
How do you manage gap risk?
Not with the stop, since the stop is exactly what stops working. You manage it beforehand, with size and exposure.
- Identify risky moments. Central bank decisions, major releases, weekends, holidays.
- Decide exposure in advance. Close, reduce, or hold knowingly. A written rule beats a decision taken a minute before the release.
- Size for the gap scenario. If a position stays open through an event, calculate the loss for a plausible gap (say 3 to 5 times the stop distance), not just for the stop.
- Beware of "guaranteed" levels. A pegged rate, a level defended by a central bank, a historic support: the safer it looks, the more stops pile up, and the harder the fall if it gives way.
- Know your protections. Some brokers offer guaranteed stops for a premium. Negative balance protection, where it applies, caps the loss at your account, not at your planned risk.
The limits of the lesson
- The event was extreme. A move this size on a major pair is rare. It does not justify trading without a stop; it shows what a stop does not cover.
- Figures vary by source. Low reached, slippage suffered, broker losses: amounts differ across platforms and statements. They are given here as orders of magnitude.
- The date was not predictable. The risk was: a level held by one policy decision can be dropped by another.
This content is educational and is not investment advice. Trading involves a risk of capital loss.
Measuring your slippage on Trade Stack
On Trade Stack, you enter your planned risk, your stop and your actual exit price. Each trade's realised R is your actual P&L divided by your planned risk: a stop planned at −1 R that costs $160 instead of $100 shows up at −1.6 R, trade after trade. Over a month, you know what slippage really costs you, and around which events.
Track my real exits on Trade Stack
Key takeaways
- On January 15, 2015, the SNB dropped the 1.20 floor and EUR/CHF fell toward 0.85 within minutes.
- Stops were filled wherever a buyer reappeared, often hundreds of pips lower.
- A stop is an order, not a guarantee: it states the price you want, not the price you will get.
- Gap risk is managed beforehand, through size and exposure, not through the stop.
- The safer a level looks, the more stops pile up beneath it.
Sources: Swiss National Bank statements of September 6, 2011 (floor introduced) and January 15, 2015 (floor removed); Jean-Pierre Danthine's statement of January 12, 2015; FXCM statement of January 15, 2015 (about $225 million in negative client balances); Alpari UK administration on January 19, 2015; ESMA product intervention measures on CFDs (2018). Price levels are orders of magnitude and vary by platform. Slippage table: example calculation.
