South Korea’s benchmark KOSPI index (KS11) plunged 7.2% in intraday trading on March 4, 2026, marking its steepest single-day drop in history as geopolitical tensions in the Middle East triggered a global risk-off rally. Energy and defense stocks bore the brunt of the sell-off, with XLE and related defense equities falling over 10% amid rising volatility.
- KOSPI (KS11) dropped 7.2% intraday on March 4, 2026—its largest daily decline ever.
- XLE fell 10.3% amid rising oil supply concerns, with CL=F spiking to $89.30 per barrel.
- Defense-related equities declined over 12% as regional conflict intensified.
- Korean won weakened to 1,387.50 per USD, its weakest level since 2022.
- Regional indices in Japan and Taiwan also fell over 3% amid spillover effects.
- Market volatility is expected to persist until geopolitical risks ease.
South Korea’s financial markets experienced unprecedented turmoil on March 4, 2026, as the KOSPI index (KS11) dropped 7.2% intraday, the largest single-day decline in its history, following a sharp escalation in the Middle East conflict. The selloff unfolded across trading floors in Seoul, with foreign exchange dealers at institutions like Hana Bank reporting heightened stress amid rapid capital outflows and a surge in currency volatility. The sell-off was catalyzed by fears of broader regional spillover, particularly concerning energy supply chains and shipping routes in the Red Sea and Persian Gulf. The energy sector was among the hardest hit, with the S&P Energy Sector ETF (XLE) falling 10.3% in global trading, reflecting market concerns over potential disruptions to crude oil flows. Crude oil futures (CL=F) surged 5.8% during the session, reaching $89.30 per barrel, as traders priced in increased supply risk. Defense-related equities also declined sharply, with major Korean defense contractors seeing losses exceeding 12%, as investors reassessed risk exposure to geopolitical instability. Market participants noted that the sell-off was not confined to Korea, with regional indices in Japan and Taiwan also experiencing declines exceeding 3%. The Korea Composite Stock Price Index (KS11) closed down 6.5% for the day, erasing gains from the prior quarter and signaling a shift from a previously elevated risk appetite. The Korean won weakened to 1,387.50 per U.S. dollar, its weakest level since 2022, as foreign investors exited local assets. The rapid repricing underscores the fragility of global equity markets under severe geopolitical stress. Energy, defense, and logistics stocks are now under renewed scrutiny, with analysts warning of sustained volatility until regional tensions stabilize. Market participants are closely monitoring U.S. Fed policy signals, given the confluence of inflationary pressures from oil shocks and a potential slowdown in global growth.