Seoul — August 27, 2026. Published after the market close; Korean index and stock prices are official closing values, while continuously traded quotes such as FX and oil are indicative session levels.
The 30-second version
- The KOSPI closed at 6,912.37, up 1.53% (+104.16 points) — a third straight day of gains for the benchmark; the small-cap KOSDAQ rose 1.30% to 837.65.
- Nvidia’s earnings beat overnight (adjusted EPS of $2.22 vs. $2.10 expected, plus above-consensus revenue guidance) drove the index up as much as 2.76% to 6,996.12 in early trade.
- The rally lost steam mid-session when the Bank of Korea announced a base-rate increase at its Monetary Policy Board meeting, injecting caution into a hot market.
- Batteries, not chips, were the day’s biggest winners: Samsung SDI jumped 10.27% and LG Energy Solution 5.56% on reports the government is reviewing a larger energy-storage (ESS) tender.
- Foreign investors were net buyers today, but remain net sellers of roughly KRW 6.07 trillion (~$4.4 billion) over the five sessions through August 26.
Nvidia lit the fuse; the Bank of Korea trimmed it
Korea is arguably the most Nvidia-sensitive stock market outside the US, because its two index heavyweights — Samsung Electronics and SK hynix — supply the memory chips that AI accelerators depend on. So when Nvidia reported fiscal 2027 second-quarter adjusted EPS of $2.22, ahead of the $2.10 consensus, and guided third-quarter revenue above expectations, Seoul opened strong. The KOSPI touched 6,996.12 — within sight of the 7,000 line — before settling back.
What cooled things off was domestic: the Bank of Korea’s Monetary Policy Board, which met today, announced a base-rate increase during the trading session. A rate hike raises borrowing costs across the economy and, mechanically, the discount rate investors apply to future earnings — so even on a bullish day, it acts like a hand on the brake. The index still finished up 1.53%, and chipmakers held their gains: Samsung Electronics closed up 1.72% at 266,000 won, SK hynix up 2.49% at 1,730,000 won, and chip-equipment maker Hanmi Semiconductor up 1.14%.
Context matters here. August has been a whipsaw month — a 5.80% plunge on the 19th, a 5.89% rebound on the 20th, another 3.12% drop on the 24th. Today’s close puts the KOSPI back almost exactly at its August 21 level of 6,912.95. The market has recovered the damage, not broken new ground.
The won firmed modestly, with the Seoul close reported at 1,380.9 per dollar, down 3.9 won. (The global 24-hour feed showed 1,380.56; the two can differ slightly.)
Batteries stole the semiconductor story’s thunder
The single biggest mover among large caps was Samsung SDI, up 10.27% to 569,000 won. LG Energy Solution gained 5.56%, and battery-materials names EcoPro and EcoPro BM rose 5.75% and 5.83%. The trigger was news that the government is reviewing an expansion of its ESS — grid-scale energy storage — tender program, while power-equipment shares also rallied on expectations of North American grid-replacement demand.
Sector data (using KODEX sector-ETF proxies, which can deviate slightly from official sector indices) shows 5 of 8 groups advanced: Secondary Battery +5.84%, Steel +2.12% (POSCO Holdings gained 3.51%), Semiconductors +2.00%, Construction +1.26%, Banks +0.53%. The clear laggard was Autos at -2.69% — Kia fell 4.03% and Hyundai Motor 2.45%, and game maker Krafton dropped 3.73%.
Flows: foreigners bought today, but the week still belongs to the sellers
By today’s exchange tallies, foreign investors net bought about KRW 142.2 billion (~$100 million) on the KOSPI and KRW 88.4 billion on the KOSDAQ, with institutions adding KRW 177.6 billion and 61.7 billion respectively. Retail investors took profits, net selling roughly KRW 1.92 trillion (~$1.4 billion) on the KOSPI alone.
Zoom out, though, and foreigners have net sold about KRW 6.07 trillion (~$4.4 billion) over the five sessions through August 26. In the previous session (August 26, KOSPI and KOSDAQ combined), individuals dumped KRW 2.25 trillion while institutions absorbed KRW 761.5 billion — most of it brokerage proprietary desks, with pension funds slightly negative — and other corporations bought KRW 1.60 trillion. Meanwhile, sidelined cash remains deep: investor deposits stood at KRW 102.5 trillion (~$74 billion) and margin-loan balances at KRW 32.8 trillion as of August 25.
On the disclosure front, the day’s notable regulatory filings included preliminary earnings from the HD Hyundai shipbuilding group — see the HD Hyundai Heavy Industries filing — and a cash dividend decision from LG Corp, alongside merger-filing corrections from SK Gas and SK Discovery and a convertible-bond issuance decision at KG Mobility.
Today’s closing numbers
| Item | Close | Change |
|---|---|---|
| KOSPI | 6,912.37 | +1.53% |
| KOSDAQ | 837.65 | +1.30% |
| USD/KRW (Seoul close) | 1,380.9 | -3.9 won |
| Samsung Electronics | 266,000 | +1.72% |
| SK hynix | 1,730,000 | +2.49% |
| Samsung SDI | 569,000 | +10.27% |
| LG Energy Solution | 370,500 | +5.56% |
| Kia | 126,100 | -4.03% |
| VIX | 14.93 | -1.84% |
| WTI crude ($/bbl, indicative) | around 80.9 | down roughly 1.7% |
| S&P 500 (prev. US session) | 7,675.70 | -0.02% |
What to watch next
- September 1: Korea customs 10-day trade data. The exports flash is the first hard read on whether the AI-chip demand the market is pricing in shows up in actual shipments.
- Foreign flows. One day of buying does not offset KRW 6.07 trillion of selling over five sessions — watch whether today marks a turn or a pause.
- Follow-through on the ESS story. Battery names priced in a policy review today; details of any actual tender expansion will decide if the move sticks.
- Rate-hike digestion. How the won, banks, and construction names trade in the coming sessions will show how much tightening the market can absorb.
- Shipbuilders’ numbers. The HD group’s preliminary-earnings filings deserve a closer read once full figures circulate.
FAQ
Why did the KOSPI rise on August 27, 2026?
Nvidia’s earnings beat revived AI-chip sentiment, lifting Samsung Electronics and SK hynix, while battery stocks surged on reports of an expanded government ESS tender. The index gained 1.53% to 6,912.37, though a mid-session Bank of Korea rate hike trimmed an early 2.76% advance.
What did the Bank of Korea decide today?
Its Monetary Policy Board announced an increase in the base rate during the trading session. The new level was not specified in our source data, but the announcement visibly cooled the morning rally.
Why did Samsung SDI jump over 10%?
News that the government is reviewing a larger energy-storage (ESS) tender program sparked broad buying of battery makers — Samsung SDI rose 10.27%, LG Energy Solution 5.56%, and EcoPro and EcoPro BM each gained more than 5.7%.
Are foreign investors buying Korean stocks again?
Today, yes — roughly KRW 142.2 billion of net buying on the KOSPI and KRW 88.4 billion on the KOSDAQ. But over the five sessions through August 26 they were net sellers of about KRW 6.07 trillion (~$4.4 billion), so the trend has not yet reversed.
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.
Related reading
Also on Seoul Closing Bell
A companion piece on the same session, written from a different angle: Bank of Korea Hikes to 3% and the KOSPI Stalls at 7,000.