South Korea’s stock market is becoming harder for global investors to ignore as the AI boom increases demand for shares of the country’s major semiconductor companies. Its trading hours, however, have remained largely tied to the Korean business day.
That is beginning to change. Korea Exchange, the operator of South Korea’s main stock markets, will open a real time evening session from 4 p.m. to 8 p.m. beginning Sept. 14, allowing investors to trade most Kospi and Kosdaq stocks several hours after the regular market closes.
The shift could be particularly important as Samsung Electronics, South Korea’s largest electronics and memory chip company, and SK Hynix, a leading supplier of high bandwidth memory used in AI systems, draw greater attention from investors following the global semiconductor cycle. Longer trading hours give overseas investors more time to react to developments that occur after Seoul’s regular session ends at 3:30 p.m.
KRX will replace its existing after hours system, which matches orders every 10 minutes between 4 p.m. and 6 p.m., with continuous real time trading. Most of the 2,766 stocks listed on the Kospi and Kosdaq will be eligible, excluding securities under special market supervision. Exchange traded funds and exchange traded notes will remain unavailable.
The move also opens a new front in competition with Nextrade, South Korea’s first alternative stock trading platform. Nextrade already operates a premarket from 8 a.m. to 8:50 a.m. and an evening session until 8 p.m., but its after hours market currently offers about 600 stocks.
Nextrade has grown quickly since entering the market and accounted for about 18% of average daily trading volume between July 1 and Sept. 9. Its rise has challenged a market long dominated by KRX and pushed South Korea toward a system in which investors can choose between competing trading venues.
KRX will have an advantage in the number of stocks available during the evening, while Nextrade charges trading fees about 30% below those of KRX and will continue to hold an advantage in morning trading. KRX does not plan to introduce its own premarket until the end of next year.
Lower liquidity during evening hours remains a concern. KRX will not allow market orders and will instead limit investors to specified types of limit orders to reduce the risk of trades being executed at sharply unfavorable prices.
The exchange does not expect longer hours alone to produce an immediate surge in trading. Institutional use of evening sessions remains limited, and Nextrade has already introduced many investors to trading outside regular hours.
The broader significance is that South Korea is beginning to adjust its market infrastructure as its largest companies become more closely tied to global AI and semiconductor investment. KRX says it will continue studying longer trading schedules overseas and could eventually move toward a market operating close to 24 hours a day.
