The first U.S. market-wide circuit breaker of the COVID-19 stock-market crash halted trading on March 9, 2020.
The S&P 500 fell 7% shortly after trading began, triggering a Level 1 circuit breaker and a 15-minute pause. The drop followed escalating fears about the coronavirus pandemic and a sharp collapse in oil prices after Saudi Arabia and Russia clashed over production policy.
U.S. exchanges used circuit breakers to slow panic selling and give investors time to assess rapidly changing information. The mechanism was introduced after the 1987 crash and was later revised, including thresholds based on percentage moves in the S&P 500.
Three additional U.S. market-wide halts occurred during the crash: March 12, March 16, and March 18. The March 9 halt was the first, so it should not be confused with the later dates or with the market’s February 2020 peak.