Taiwan vs. South Korea: Diverging Paths in the Global AI Boom

As 2026 enters its final months, the two Asian economies most closely tied to the global artificial intelligence revolution are moving in very different directions. South Korea and Taiwan have both ridden the AI wave to extraordinary gains, yet where the Kospi has grabbed headlines, the Taiex has delivered stronger, broader, and more sustained performance, beating its Korean counterpart by roughly 23 percentage points last quarter, the widest margin since the turn of the century. For investors, the choice is no longer simply about which market is growing faster; it is about which growth is built to last.

The Performance Gap Widens

The numbers tell a striking story. Taiwan’s benchmark index is up 72% in 2026, making it the top performer among more than 90 global indices tracked by Bloomberg. The Kospi is not far behind at 65%, but beneath those headline figures lies a growing divergence. In the three months ending September, shares of market leaders Samsung Electronics and SK Hynix fell between 19% and 33%, snapping a six-quarter winning streak driven largely by surging memory chip prices. By contrast, Taiwan Semiconductor Manufacturing Company (TSMC) rose for a sixth consecutive quarter, and roughly 10% of all Taiex stocks have at least doubled this year compared with just 4.1% of Kospi-listed companies. Earnings upgrades across Taiwan’s market have also outpaced those for South Korea for the first time since March 2025.

Fund managers are voting with their capital: in Bank of America’s September survey, 40% of respondents said they were overweight Taiwan, while only 25% held the same view for South Korea. When asked which market would benefit most from the next phase of the AI cycle, 35% chose Taiwan, and just 5% picked South Korea.

Volume vs. Price: The Fundamental Difference

The distinction, as M&G Investments portfolio manager Vikas Pershad puts it, is not simply how much AI exposure each market has; it is where the earnings come from. Taiwan’s gains stretch across chip design and manufacturing, packaging, networking, and servers. Its earnings growth is driven by rising volume, more units shipped, more systems deployed, more infrastructure built which makes upgrades both broader and more durable. South Korea’s market, by contrast, is dominated by two giants: Samsung and SK Hynix. Its recent earnings surge has come from rising prices for memory chips, a dynamic that can reverse as quickly as it arrived.

Société Générale strategists, led by Rajat Agarwal, sum it up plainly: they maintain a clear preference for Taiwan “given the diverging earnings growth trajectories.” Memory price appreciation is expected to slow through 2027, they note, before normalising in 2028 and as Chinese production capacity expands, competitive pressure will only increase. South Korea’s broader market retreat since July reinforces these concerns: what began as deleveraging has widened into a broader investor withdrawal.

The Counter‑Argument: HBM and the AI Lifeline

Not everyone is bearish on Korea. Optimists argue that AI demand itself will sustain the upcycle, particularly for high‑bandwidth memory (HBM) the advanced chips essential to running large language models. Citigroup’s Peter Lee believes the market is underestimating just how much HBM will be needed in 2027, and that Samsung and SK Hynix remain uniquely positioned to supply it. On this view, the recent pullback is an overreaction a buying opportunity in companies that will remain indispensable to the AI era.

Valuation, Discount, and Perception

The contrast extends to how these markets are priced. The Taiex trades at roughly 18 times its one‑year forward earnings estimate a premium that reflects confidence in its diversified growth engine. The Kospi trades at just 5.5 times, a discount born partly from fears that the memory cycle is nearing its peak, and partly from the longstanding “Korea discount” structural concerns around corporate governance, concentration risk, and volatility that have kept valuations depressed relative to global peers for years.

Taiwan’s next phase of growth, as Allspring Global Investments portfolio manager Gary Tan observes, will depend less on broad AI enthusiasm and more on the reality of the supply chain itself on companies solving genuine bottlenecks and delivering essential components. That is both its strength and its anchor: it is built not on a single product category or price trend, but on being the indispensable foundation of the world’s most advanced technology. South Korea, meanwhile, stands at a crossroads: will HBM demand extend the upcycle, or will reliance on memory expose it when the tide turns? For investors, the choice is becoming clearer and the gap is widening.