South Korean brokerages are set to offer virtually round-the-clock trading in US stocks from Dec. 6, by combining Nasdaq's expanded 23-hour trading schedule with an additional hour through alternative trading platform Blue Ocean.
According to financial industry sources, Korean brokerages and the Korea Securities Depository are preparing for the expanded system.
The KSD said it would support brokerages by asking its local custodian, Citibank, to strengthen monitoring and ensure smooth settlement, while expecting minimal impact on staffing and operating costs.
The move follows the US Securities and Exchange Commission's approval in April of Nasdaq's plan to extend trading hours to 23 hours a day, five days a week. The expanded session is scheduled to begin at 9 p.m. Eastern Time on Sunday, Dec. 6, ahead of the next trading day, corresponding to 11 a.m. KST on Monday, Dec. 7.
The shift will include ETFs, with NYSE Arca, an electronic exchange operated by NYSE Group and a major venue for ETF listings, set to extend its trading hours to 23 hours a day from Dec. 6.
South Korea stands out for its broad adoption, with all domestic brokerages set to support the expanded schedule from day one. By combining Nasdaq's 23-hour trading window with existing alternative trading systems, including Blue Ocean, to cover the remaining hour, Korean brokerages will offer retail investors virtually uninterrupted access to US stocks.
Meanwhile, brokerages in other markets are taking a more cautious approach. In Japan and Taiwan, adoption is expected to be limited to a few major or foreign-focused firms, while activity in China remains largely institutional.
In Europe, Australia and New Zealand, global and fintech platforms are leading adoption as traditional retail firms cite liquidity and operational concerns. Across Southeast Asia, local brokerages have largely shelved plans, leaving access mainly to high-net-worth clients through global trading desks.
For Korean brokerages, offering 24-hour trading is a natural step given local investors' strong demand for US stocks. According to KSD data, Korean investors' net purchases of US stocks reached $2.20 billion over the four trading days from Nov. 2 to 6. That exceeded August's $1.96 billion, more than doubled September's $1 billion and amounted to about 40 percent of October's $5.42 billion.
Industry officials say the significance of the overhaul goes beyond extending trading hours: it brings daytime trading, which previously relied on third-party ATS platforms, into Nasdaq's official trading session.
"Daytime trading, which has so far been conducted through three alternative trading platforms โ Blue Ocean, Bruce and Moon โ will expand to include the New York Stock Exchange and Nasdaq," a brokerage official said. "Depending on their individual agreements, brokerages will receive real-time market data from the NYSE or Nasdaq, further strengthening their daytime trading infrastructure."
The expansion of US trading hours is also expected to put Nasdaq in more direct competition with the Kospi, according to brokerage analysts.
"Nasdaq's move to 23-hour trading will challenge the assumption that the domestic stock market is the only market open during Korean daytime hours. With cryptocurrency exchanges already operating around the clock, Nasdaq's regular session will become a direct competitor to the Kospi," said Park Woo-yeol, senior researcher at Shinhan Securities.
As competition among global markets intensifies, the Korea Exchange is also planning to gradually extend its trading hours toward round-the-clock trading. At Korea Premium Week in September, the exchange announced a phased plan to introduce 24-hour trading.
"We plan to build the IT infrastructure for a single trading board by the end of 2027. We will first work to establish a 12-hour trading system by opening a premarket session ahead of regular trading hours," said Jin Dong-hwa, deputy head of the Kospi Market Division at the KRX.
