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

Joint intervention pushes won to its strongest level in nine months

Strong demand for the won, fueled by inflows into South Korea's foreign-exchange market from the listing of SK Hynix American depositary receipts and a return by foreign investors to net buying of local stocks, drove the won-dollar exchange rate down 141 won, or 9%, in a month. Late on July 30, South Korea, the US and Japan also carried out their first coordinated intervention in the foreign-exchange market, lifting the won to its strongest level in nine months.

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

The won had weakened to as low as 1,559.2 per dollar during trading on July 1 before rebounding 141.2 won over the following month. Coordinated market intervention by South Korea, the US and Japan added to the decline in the exchange rate on the final day of July. South Korean and Japanese foreign-exchange authorities are believed to have intervened at around the same time by buying won and yen and selling dollars. The US also conducted a so-called rate check at a similar 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)