Korea Exchange after-hours debut triggers 1,637 volatility halts
The Korea Exchange's expanded after-hours session on Monday processed ₩1.8 trillion (US$1.3 billion) in trades, with observers linking a surge in price control activations to lower liquidity.
KRX Expands Trading Hours
The Korea Exchange (KRX) launched an expanded after-hours trading session on Monday, 14 September 2026, aiming to boost its global competitiveness and offer more trading options for investors. The session, running from 4 p.m. to 8 p.m., processed 72.24 million shares valued at ₩1.8 trillion (US$1.3 billion).
This volume contrasts with the regular Monday trading session, which saw 905 million shares worth ₩25.8 trillion change hands.
Volatility Halts Surge
During the initial after-hours session, the KRX reported 1,637 activations of its volatility interruption (VI) mechanisms. These mechanisms temporarily shift a stock to a single-price auction for approximately two minutes when its price moves significantly, designed to curb excessive market swings.
For comparison, the regular trading session on the same day triggered VIs 400 times. Excluding simultaneous static and dynamic VI triggers, the after-hours count was 1,112, compared to 391 in regular trading.
Liquidity Concerns Cited
Market observers attribute the increase in volatility during after-hours trading to reduced liquidity. The KRX significantly expanded the number of stocks available for after-hours trading to 2,459, up from 606 previously offered on NXT's after-hours market.
While most KOSPI and KOSDAQ stocks are now tradable, the KRX has excluded exchange-traded funds (ETFs) and exchange-traded notes (ETNs) from the four-hour session due to concerns over potential market volatility.
KRX Monitors Market Stability
Despite the sharp rise in volatility interruptions, the KRX stated that prices generally remained stable. The average high-low volatility for KOSPI stocks was 2.9 percent during after-hours, against 4.1 percent in regular trading. For KOSDAQ stocks, it was 4.6 percent after-hours compared to 5.8 percent regularly.
The exchange applied the same VI thresholds as regular trading to ensure stable operations, acknowledging that after-hours markets typically feature lower liquidity and higher volatility. The KRX plans to closely monitor market conditions and gather feedback to help the new market segment settle.
This article is journalism, not investment advice; consult a licensed professional before making financial decisions. Market data is indicative, may be delayed, and should be verified with your broker or exchange before use.
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