The KOSPI climbed from 4,214.17 at the end of 2025 to 9,114.55 in June before semiconductor losses and leveraged selling pulled it back to 5,593.56.
South Korea's KOSPI ended the July 30, 2026 regular session 1.2% lower at 5,593.56. That was 3,520.99 points, or 38.63%, below its record closing high of 9,114.55 set on June 22. The move took just 38 days.
The latest decline was also rapid. The KOSPI fell for three consecutive sessions from July 28 through July 30, losing 17.20% from its July 27 close of 6,755.75. The move stands out not only for the three-day rout, but also because it reversed a substantial part of a rally that had more than doubled the index between the end of 2025 and June.
From 4,214 to 9,114 in less than six months
The KOSPI ended the final trading day of 2025 at 4,214.17. It went on to cross 5,000 on January 22, 6,000 on February 25 and 7,000 on May 6. The index traded above 8,000 for the first time intraday on May 15 and recorded its first close above that level on May 26. It then closed above 9,000 for the first time at 9,063.84 on June 18.
Four days later, on June 22, the KOSPI reached an intraday high of 9,253.00 and set its record close at 9,114.55. That represented a 116.28% gain from the end of 2025. It took less than five months for the index to go from its first move through 5,000 to its first close above 9,000.
A 38.63% decline in 38 days
The July 30 close of 5,593.56 was 38.63% below the June record. After gaining 4,900.38 points from the end of 2025 to the peak, the index gave back 3,520.99 points in 38 days. Even after that decline, it remained 32.73% above its 2025 year-end close.
Both legs of the move were therefore fast. The latest three sessions marked a sharp acceleration of the decline that followed the June peak.
The latest three-session drop reached 17.20%
| Session | KOSPI close | Regular-session move |
|---|---|---|
| July 28 | 6,023.66 | -10.84% |
| July 29 | 5,663.24 | -5.98% |
| July 30 | 5,593.56 | -1.2% |
The Korea Exchange triggered a marketwide circuit breaker on the morning of July 28 after the KOSPI fell more than 8% from the previous close, halting trading for 20 minutes. The KOSPI also fell more than 8% intraday on July 29. Bloomberg reported that circuit breakers were triggered in both the KOSPI and Kosdaq markets for a second consecutive session.
Samsung Electronics and SK hynix led the decline
On July 28, Samsung Electronics closed 13.39% lower at 220,000 won and SK hynix fell 14.65% to 1.55 million won. Reuters reported that the two companies represented more than half of the KOSPI's market capitalization, giving their declines an outsized effect on the benchmark.
SK hynix dropped another 9.4% on July 29, while Samsung Electronics lost 4.8%. SK hynix reported quarterly revenue of 79.3187 trillion won and operating profit of 60.5426 trillion won that day. Operating profit rose 557% from a year earlier to a record, but the Associated Press reported that it fell short of market expectations and the shares continued lower after the release.
On July 30, Samsung Electronics declined 0.7% after reporting second-quarter operating profit of 89.5 trillion won. SK hynix fell another 5.6% in the same session.
AI spending and Chinese competition were both in focus
The July 28 selling followed declines in semiconductor shares in the United States and across Asia. Market participants focused on how quickly revenue from AI services could support technology companies' expanding infrastructure spending.
The Shanghai listing of Chinese memory-chip maker CXMT and reports about Chinese development of deep-ultraviolet lithography equipment added to competition concerns. Reuters reported that investors focused on CXMT's potential to expand production after the listing and on advances in China's chipmaking capabilities.
Chi Lo, senior Asia-Pacific market strategist at BNP Paribas Asset Management, told the Associated Press that volatility in AI-related stocks in South Korea, Taiwan and Japan reflected questions about technology companies' AI spending and whether it could generate sustainable returns. He said improving competition from Chinese AI companies had revived those concerns.
Borrowed positions added to the selling
Reuters reported that retail investors had increased borrowed exposure during the rally in Korean semiconductor shares and that brokers forcibly closed some losing positions as prices fell.
Frank Benzimra, head of Asia equity strategy at Societe Generale, described the move to Reuters as the unwinding of a crowded trade and said the stocks with the most leverage had fallen the most. Han Ji-young, an analyst at Kiwoom Securities, said hopes for a rebound after the July 28 plunge faded and additional selling followed on July 29.
Tighter single-stock leverage rules take effect July 31
Before the three-session decline, South Korea's Financial Services Commission announced on July 24 that it would move up tighter deposit requirements for single-stock leveraged ETFs and ETNs to July 31. Retail investors making new or additional purchases must hold at least 30 million won in cash. The previous requirement was 10 million won and allowed some stocks, ETFs and bonds to count as substitute collateral.
The authorities had already stopped new listings and advertising of single-stock leveraged products on July 16. From July 31, substitute securities will no longer count toward the minimum deposit and brokerages will not be allowed to reduce the requirement based on an investor's trading experience.