South Korean Banks Earn Record 32.2 Trillion Won in Interest as Securities Losses Cut First-Half Profit 6.4 Percent
South Korea’s domestic banks generated a record 32.2 trillion won in interest income in the first half of 2026, yet stronger core banking earnings were not enough to prevent net profit from falling, as higher market interest rates produced substantial securities losses.
The Financial Supervisory Service said the 20 domestic banks posted 13.8 trillion won in net profit in preliminary first-half results, down 6.4 percent from 14.7 trillion won a year earlier. Interest income rose by 2.5 trillion won, or 8.3 percent, while non-interest income dropped 43.4 percent to 2.9 trillion won.
| Indicator | H1 2026 | H1 2025 | Change |
|---|---|---|---|
| Net profit | 13.8tn won | 14.7tn won | −6.4% |
| Interest income | 32.2tn won | 29.7tn won | +8.3% |
| Non-interest income | 2.9tn won | 5.2tn won | −43.4% |
| Interest-earning assets, average | 3,628.1tn won | 3,409.5tn won | +6.4% |
| Net interest margin | 1.56% | 1.52% | +4bp |
Average interest-earning assets expanded 6.4 percent to 3,628.1 trillion won, while the net interest margin widened four basis points to 1.56 percent. Interest income therefore grew almost two percentage points faster than the earning-asset base, reflecting both balance-sheet expansion and improved interest profitability.
The pressure came from elsewhere. Securities-related earnings moved from a 3.2 trillion won profit in the first half of 2025 to a 2.5 trillion won loss, a negative swing of 5.7 trillion won as higher market yields reduced bond valuations. That swing was about 2.3 times the entire increase in interest income and more than six times the decline in net profit, our calculation.
| Earnings bridge, year on year | Change |
|---|---|
| Interest income | +2.5tn won |
| Securities-related earnings | −5.7tn won |
| Net profit | −0.9tn won |
The distinction matters. The headline 6.4 percent profit decline did not signal weakness in the banks’ core spread business, where lending and other interest-bearing assets generated materially more income. The principal offset was the effect of higher market rates on the value of securities the banks hold.
The securities hit did not flow one for one into net profit because other non-interest lines performed well. Foreign-exchange and derivatives income climbed 86.8 percent to 5.0 trillion won and fee income rose 18.0 percent to 3.3 trillion won, while selling and administrative expenses increased 5.4 percent to 14.4 trillion won and loan-loss expenses rose 8.6 percent to 3.5 trillion won.
Separate FSS data released on 21 August showed the domestic-bank won-loan delinquency rate at 0.56 percent at the end of June, four basis points above the 0.52 percent recorded a year earlier but down sharply from 0.67 percent in May. The monthly improvement needs context: banks disposed of 5.3 trillion won of delinquent loans in June, against 1.5 trillion won in May, while newly delinquent loans fell to 2.6 trillion won from 3.3 trillion won.
| Asset quality | May 2026 | June 2026 |
|---|---|---|
| Delinquency rate | 0.67% | 0.56% |
| New delinquencies | 3.3tn won | 2.6tn won |
| Delinquent loans resolved | 1.5tn won | 5.3tn won |
June disposals were therefore roughly 2.0 times new delinquencies, against less than half of new delinquencies in May, so the fall in the headline ratio was helped materially by quarter-end write-offs and sales rather than by arrears disappearing, our reading.
Why it matters: The first half shows a bank system whose recurring earnings engine is strengthening, with record interest income, a larger earning-asset base and wider margins, while the securities swing was the largest single offset to those stronger core earnings rather than evidence of weaker lending income. That composition is more reassuring than a 6.4 percent profit drop suggests, because it points to a valuation effect rather than a deterioration in lending income, though rising loan-loss expenses and a delinquency rate still above a year earlier show that credit costs are the genuine watch item.
Outlook: The second half turns on two variables: whether market-rate volatility moderates enough to ease the securities drag while the stronger interest-income base persists, and whether asset quality holds once quarter-end disposals no longer flatter the delinquency ratio. Sustained interest-income growth with contained credit costs would restore profit growth; a further rise in arrears would absorb more of the benefit through provisioning.
Sources: Financial Supervisory Service, 21 and 23 August 2026.
