On what date did the S&P 500 reach its COVID-19 crash low in the United States?

The S&P 500 reached its COVID-19 crash low on March 23, 2020.

The index closed at 2,237.40 that day, after falling rapidly from its February 19 record close. The collapse reflected the spread of COVID-19, lockdowns, travel restrictions, business closures, an oil-price shock and intense uncertainty about the global economy. The S&P 500 had entered a bear market in March, meaning a decline of at least 20% from a recent high.

The Federal Reserve and governments introduced extraordinary monetary and fiscal support. Interest-rate cuts, asset purchases, emergency lending programs and large relief packages helped stabilize markets. As investors began anticipating vaccines and economic reopening, US equities recovered unusually quickly compared with many earlier crashes.

March 23 is sometimes confused with March 9 or March 16, which were also severe trading days. It is also important to distinguish the S&P 500's closing low from intraday lows and from the Dow's separate records. The crash was global, but this question refers specifically to the US S&P 500 index.