Key Takeaways
- • South Korean won depreciated to 1,500+ per US dollar in late March 2026, marking its weakest level since March 2009 (17-year low), driven by escalating US-Iran geopolitical tensions and risk-off sentiment across Asian markets.
- • Foreign investors executed aggressive equity liquidation, with net outflows totaling 1.8 trillion won in initial selling waves and subsequent sessions recording 7.7 trillion won in KOSPI share sales across seven consecutive trading days, creating sustained downward currency pressure.
- • South Korea's energy import dependency amplified vulnerability to oil price volatility stemming from Strait of Hormuz disruption risks, while domestic industrial production contracted 0.3% in May with semiconductor output declining 10%, compounding economic headwinds.
- • The South Korean government and ruling party mobilized a 25 trillion-won supplementary budget to mitigate rising energy costs and support vulnerable populations, signaling fiscal policy response to the currency crisis.
- • Subsequent diplomatic de-escalation between the US and Iran eased supply disruption concerns, providing temporary relief to the won and broader Asian market sentiment, though the currency remained significantly weakened from pre-crisis levels.
Summary
The South Korean won reached its lowest valuation in 17 years during late March 2026, breaching the 1,500 per US dollar threshold as geopolitical tensions in the Middle East triggered a sharp risk-off rotation across Asian financial markets. The primary catalyst was escalating US-Iran hostilities, with the US imposing a 48-hour deadline for Iran to reopen the Strait of Hormuz and threatening strikes on Iranian energy facilities, while Iran countered with threats to close the strait and target regional energy and water infrastructure.
Foreign institutional investors responded with substantial equity liquidation. Initial sessions recorded net outflows of 1.8 trillion won, with subsequent trading days seeing record KOSPI share sales of 7.7 trillion won across seven consecutive sessions. This persistent foreign selling created sustained downward pressure on the currency independent of macroeconomic fundamentals. The won's weakness was further reinforced by broader Asian market deterioration and safe-haven demand for US dollar positioning.
South Korea's structural vulnerability to energy price shocks amplified the currency's decline. As a net energy importer with limited domestic petroleum reserves, any disruption to Strait of Hormuz traffic directly threatens input costs and economic stability. Compounding these external pressures, domestic industrial production contracted 0.3% in May 2026, with semiconductor output falling 10% due to shipment adjustments and statistical base effects, signaling underlying economic weakness.
In response, the South Korean government and ruling party prepared a 25 trillion-won supplementary budget designed to absorb rising energy costs and provide support to economically vulnerable segments. Subsequently, renewed diplomatic engagement between the United States and Iran alleviated immediate concerns regarding oil supply disruptions, moderating additional won depreciation and providing modest relief to market sentiment, though the currency remained substantially weaker than pre-crisis levels.
Foreign institutional investors responded with substantial equity liquidation. Initial sessions recorded net outflows of 1.8 trillion won, with subsequent trading days seeing record KOSPI share sales of 7.7 trillion won across seven consecutive sessions. This persistent foreign selling created sustained downward pressure on the currency independent of macroeconomic fundamentals. The won's weakness was further reinforced by broader Asian market deterioration and safe-haven demand for US dollar positioning.
South Korea's structural vulnerability to energy price shocks amplified the currency's decline. As a net energy importer with limited domestic petroleum reserves, any disruption to Strait of Hormuz traffic directly threatens input costs and economic stability. Compounding these external pressures, domestic industrial production contracted 0.3% in May 2026, with semiconductor output falling 10% due to shipment adjustments and statistical base effects, signaling underlying economic weakness.
In response, the South Korean government and ruling party prepared a 25 trillion-won supplementary budget designed to absorb rising energy costs and provide support to economically vulnerable segments. Subsequently, renewed diplomatic engagement between the United States and Iran alleviated immediate concerns regarding oil supply disruptions, moderating additional won depreciation and providing modest relief to market sentiment, though the currency remained substantially weaker than pre-crisis levels.
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