What Is a Circuit Breaker?
A circuit breaker is a market protection mechanism used by stock exchanges to temporarily pause trading during periods of extreme market volatility. Its purpose is to reduce panic-driven trading, maintain orderly markets, and give investors time to evaluate rapidly changing market conditions before trading continues.
Circuit breakers are widely used by major exchanges, including the New York Stock Exchange (NYSE) and Nasdaq, and are monitored under rules established by US market regulators.
There are two main types of circuit breakers:
- •Single-stock circuit breakers, which temporarily halt trading in an individual stock experiencing unusually large price movements.
- •Market-wide circuit breakers, which pause trading across the entire market when major indices experience significant declines.
Market-wide circuit breakers operate differently. If the S&P 500 Index falls by predetermined percentages during the trading day, exchanges may temporarily suspend trading across all listed securities to help stabilise the broader market.
It's important to understand that circuit breakers are not designed to prevent market declines. Instead, they help ensure trading remains fair, transparent, and orderly during periods of exceptional volatility.
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Understanding circuit breakers is an important part of becoming a more informed long-term investor, particularly when investing in global markets from Saudi Arabia or the wider GCC.