South Korean stocks plunged for a second consecutive day on March 4, triggering circuit breakers on both the KOSPI and KOSDAQ markets amid escalating Middle East conflict .
The benchmark KOSPI tumbled 12.06% to close at 5,093.54, while the KOSDAQ plummeted 14.00% to finish at 978.44—marking the steepest daily percentage drops in history for both indexes .
Circuit breakers were activated at 11:16 a.m. local time on the KOSDAQ when the index fell more than 8% for over one minute, followed by the KOSPI three minutes later, suspending trading for 20 minutes . This marks the first simultaneous triggering of circuit breakers on both major markets since August 2024 .
Market bellwethers led the decline, with Samsung Electronics plunging 11.74%, SK Hynix dropping 9.58%, and Hyundai Motor falling 15.80% .
The sell-off was triggered by geopolitical tensions in the Middle East, with concerns over Iran potentially blocking the Strait of Hormuz driving oil prices higher . As a major energy importer—sourcing over 70% of its oil from the Middle East—South Korea faces heightened vulnerability to supply disruptions .
The KOSPI had surged nearly 50% in early 2026 following last year's 75% gain, making it one of the world's best-performing markets before this week's correction . The won weakened to 1,476.2 per dollar amid the turmoil .
