Korea-US-Japan FX Coordination Drives Won to 1,418 Per Dollar

Joint intervention lifts won to a nine-month high

A surge in demand for the won, fueled by inflows into South Korea’s foreign-exchange market from SK Hynix’s American depositary receipt listing and a return to net foreign buying of local stocks, drove the won-dollar exchange rate down 141 won, or 9%, in a month. Late on July 30, the foreign-exchange authorities of South Korea, the US and Japan intervened in concert for the first time, pushing the won to its strongest level in nine months.

The won traded at 1,418 per dollar at 6 a.m. in Seoul on July 31. That was the lowest level for the won-dollar rate since Oct. 20, 2025, when it stood at 1,417.1 won per dollar. The benchmark rate was 1,424 won per dollar as of 3:30 p.m. The sharp drop in the exchange rate appears to have prompted bargain buying of dollars.

The won-dollar rate had risen as high as 1,559.2 on July 1 before falling 141.2 won over the following month. Coordinated action by South Korea, the US and Japan accelerated the drop on the final day of July. South Korean and Japanese foreign-exchange authorities are said to have intervened at roughly the same time by buying won and yen and selling dollars. The US also conducted a so-called rate check around the same time, asking market participants for trading quotes. In the market, a rate check is viewed as a signal of intervention.

Kim Ik-hwan, Hankyung.com reporter, lovepen@hankyung.com