On what date did the Nikkei 225 reach its all-time closing high before Japan’s market crash?

The Nikkei 225 reached its all-time closing high before Japan’s market crash on 29 December 1989.

The index closed at 38,915.87 on that date, ending a spectacular period of Japanese asset-price expansion. During the 1980s, booming property and share prices encouraged heavy borrowing and speculation. The Bank of Japan then tightened monetary policy, and the bubble began to deflate.

The Nikkei’s decline continued through the early 1990s, while Japan entered a prolonged period of weak growth and financial stress. Because the index later traded far below its 1989 level, the peak became a major reference point in discussions of asset bubbles.

A common mix-up is to describe 29 December as the market’s intraday high. The commonly cited record is the closing high; the Nikkei’s intraday peak occurred on 29 December as well, at a slightly higher level.