The won-dollar exchange rate fell below 1,400 won in mid-August for the first time in nearly a year, and more Koreans began buying U.S. dollars to benefit from the stronger won. The rush has lifted foreign currency deposits and boosted demand for Toss Bank’s Foreign Currency Piggy Bank. The won closed at 1,372.5 per dollar on Friday, extending its streak below 1,400 won since Aug. 19.

An employee arranges U.S. dollar and Japanese yen banknotes at Hana Bank's counterfeit detection center in central Seoul, July 2. Yonhap

When the won-dollar exchange rate fell below the 1,400-won mark in mid-August for the first time in nearly a year, Park, an office worker in her 30s, began looking for ways to buy U.S. dollars and take advantage of the stronger won.

“I came across some social media posts recommending Toss Bank’s foreign currency account as a way to make money from exchange rate movements, so I opened one,” she said. “There’s no exchange fee, and the interface is easy to use, which is especially nice for a beginner like me.”

Park is also considering dollar repurchase agreements (RPs) after watching a friend put spare cash into them whenever he had some left over. RPs are short-term investments where investors effectively lend money to a financial institution in exchange for securities that are repurchased at an agreed price and date, allowing them to earn interest on their dollars.