The stock market crash of October 1987 is commonly known by what name?

The stock market crash of October 1987 is commonly known as Black Monday. It occurred on Monday, October 19, 1987, after several days of growing pressure in financial markets. The Dow Jones Industrial Average fell 508 points, or 22.6%, in a single session—the largest one-day percentage decline in its history.

The crash spread rapidly across international markets, following a long rise in share prices and concerns about overvaluation, trade deficits, interest rates, and automated portfolio-insurance strategies. Selling overwhelmed trading systems, causing delays and temporary halts on the New York Stock Exchange.

The name can cause a geographical mix-up. Because markets opened at different times around the world, the same global event was called Black Tuesday in parts of Asia, where the local date had already advanced. In the United States and in most historical references, however, the canonical name is Black Monday.

The crash did not produce a Great Depression-style economic collapse. The Federal Reserve supplied liquidity, markets stabilized, and regulators later introduced trading curbs known as circuit breakers.