The Swiss Franc Shock of 2015: A Case Study in Hidden Risk
Posted: Sun Oct 04, 2026 9:17 am
The Swiss Franc Shock of 2015: A Case Study in Hidden Risk
On January 15, 2015, the Swiss National Bank announced it would stop defending a minimum exchange rate of 1.20 francs per euro. Within minutes, EUR/CHF fell from around 1.20 to below 0.90 at the low, before recovering partially.
For three years, the bank had capped the franc's strength, and the policy had appeared permanent. Traders treated the floor as a certainty, and many held leveraged positions assuming the pair could not fall.
The aftermath was severe. Stops failed to execute at their levels because liquidity vanished. Accounts went deeply negative. Several brokers suffered large losses, and some became insolvent or required rescue, while clients elsewhere owed money.
The lessons are lasting. First, policies that look permanent can change without warning. Second, the risk was visible: a floor held by central bank intervention is a bet that the central bank will keep spending. Third, stops are not guarantees in a gap. Fourth, leverage amplifies unknown unknowns.
The event also showed how counterparty risk becomes real in extreme events.
You cannot predict specific shocks, but you can structure your exposure assuming that one will arrive. Keep sizes moderate, avoid concentrating in pegged or capped currencies, and favor regulated brokers.
Practical step: list any positions or strategies you hold that depend on a policy or peg remaining in place, and ask what happens if it ends overnight.
On January 15, 2015, the Swiss National Bank announced it would stop defending a minimum exchange rate of 1.20 francs per euro. Within minutes, EUR/CHF fell from around 1.20 to below 0.90 at the low, before recovering partially.
For three years, the bank had capped the franc's strength, and the policy had appeared permanent. Traders treated the floor as a certainty, and many held leveraged positions assuming the pair could not fall.
The aftermath was severe. Stops failed to execute at their levels because liquidity vanished. Accounts went deeply negative. Several brokers suffered large losses, and some became insolvent or required rescue, while clients elsewhere owed money.
The lessons are lasting. First, policies that look permanent can change without warning. Second, the risk was visible: a floor held by central bank intervention is a bet that the central bank will keep spending. Third, stops are not guarantees in a gap. Fourth, leverage amplifies unknown unknowns.
The event also showed how counterparty risk becomes real in extreme events.
You cannot predict specific shocks, but you can structure your exposure assuming that one will arrive. Keep sizes moderate, avoid concentrating in pegged or capped currencies, and favor regulated brokers.
Practical step: list any positions or strategies you hold that depend on a policy or peg remaining in place, and ask what happens if it ends overnight.