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Black Wednesday 1992: the day the pound broke free

On 16 September 1992, Britain's central bank raised interest rates twice in a single day to save the pound. By evening, the government gave up. The pound left Europe's currency system, and one fund became famous for betting it would.

Story · 7-minute read · Updated 2026-10-21

The world before the crisis

In 1990, the UK joined Europe's Exchange Rate Mechanism, or ERM. The idea was to keep European currencies moving within set bands against each other, as a step towards a single currency.

The pound joined at a central rate of about 2.95 German marks. It was allowed to move only about 6% either side of that.

Here's the catch. To keep the pound inside its band, the UK had to keep its interest rates in step with Germany's.

After reunification in 1990, Germany was spending heavily to rebuild the East. To fight inflation, Germany's central bank, the Bundesbank, kept rates high.

The UK, by contrast, was in a recession. It needed lower rates. High rates made home loans more painful and slowed the economy further.

Traders began to ask a simple question: how long can Britain keep this up?

What happened

Through the summer of 1992, pressure built. The pound sat near the bottom of its band. The Bank of England bought pounds again and again to support it.

Big funds and banks started to bet the pound would fall. If it was forced out of the ERM, they would profit. If it stayed in, they'd lose relatively little, because the pound couldn't easily rise much. That's a lopsided bet, and traders love lopsided bets.

One fund, George Soros's Quantum Fund, built a very large position against the pound, by most accounts worth around $10 billion. More on him in our George Soros story.

The moment everyone remembers

Wednesday 16 September 1992 was the showdown.

• In the morning, the Bank of England bought pounds in huge amounts. The selling didn't stop.
• At about 11 am, it raised its key interest rate from 10% to 12%.
• The pound barely moved.
• In the early afternoon, it announced another rise, to 15%.
• Still the selling continued.

That evening, Chancellor Norman Lamont stepped out in front of the cameras. He said the UK was suspending its membership of the ERM. The second rate rise was cancelled. Within days, rates were back to 10%.

The pound fell sharply against the mark in the weeks that followed. Italy was forced out of the ERM at almost the same time.

Treasury papers released in 2005 estimated the cost of defending the pound at about £3.3 billion. Soros's fund is widely reported to have made more than $1 billion on the trade.

What changed afterwards

Many economists now see Black Wednesday as a turning point that helped, not hurt, the UK in the long run.

• Freed from the ERM, the UK could cut rates. The economy recovered over the following years.
• In October 1992, the UK adopted an inflation target to guide policy.
• In 1997, the Bank of England was given the power to set interest rates on its own.

Some people even started calling it "White Wednesday".

What it teaches

1. A price held up by force can fall fast

The pound's band wasn't set by buyers and sellers. It was held by a central bank spending money. When the money and the will ran out, the price moved all at once. The same thing happened to the Swiss franc in 2015: see the Swiss franc shock.

2. Interest rates move currencies

Higher rates usually make a currency more attractive. On Black Wednesday, even a jump to 15% didn't work, because traders believed it couldn't last. Read how interest rates affect stocks and our GBP/USD guide for how rates feed into prices today.

3. Lopsided risk is worth thinking about

Traders saw a trade where the downside was small and the upside large. For a beginner, the useful version is simpler: before every trade, compare how far it could go against you with how far it could go for you. That's risk-reward ratio. Try the risk-reward calculator.

What it doesn't mean

• It doesn't mean one trader "broke" the Bank of England alone. Many banks and funds were selling. Soros was the biggest and most famous, not the only one.
• It doesn't mean betting against central banks is easy money. Plenty of traders have lost doing exactly that, when the central bank won.
• It doesn't mean the outcome was bad for Britain. Many economists argue the exit allowed a healthier recovery.
• The profit and cost figures are estimates. They come from Treasury papers and press reports, not audited accounts.

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