TSMC September revenue up 54.6% YoY reinforces AI demand strength but valuation remains stretched

What happened

TSMC reported record September net revenue of NT$511.86 billion ($16.03 billion), up 54.6% year over year, extending its streak of record monthly sales and driven by strong AI chip demand. This follows a 44.7% YoY increase in July and consistent strength in August, confirming that hyperscaler AI infrastructure spending continues to convert into leading-edge wafer and packaging orders. The company's Q2 2026 gross margin was 67.7% but already reflected overseas-fab dilution, and management raised 2026 capex to $60–64 billion, pressuring near-term free cash flow. At $428.9, the stock trades at 28.6x earnings and 22.5x EV/EBITDA, leaving little margin of safety relative to our WAIT rating. The revenue print supports the base case but does not resolve the key risks of margin compression and elevated capital intensity.

Implication

For investors, the September revenue print confirms that AI demand durability remains intact, supporting the base scenario of revenue staying above 25% YoY and gross margin near 67%. However, the stock at $428.9 already discounts this strength, trading at 28.6x earnings, while elevated capex and overseas-fab dilution remain near-term headwinds. Our trim level of $470 and attractive entry of $390 still frame the risk-reward, and current prices offer limited edge. We would become more constructive only on a pullback toward $390 or clear evidence that gross margin can hold above 67% while capex converts into customer-backed utilization. Until then, we maintain a WAIT and would avoid chasing strength.

Thesis delta

The September revenue print strengthens the demand-side evidence for the base case, as growth accelerated to 54.6% YoY versus 44.7% in July, well above our 25% YoY threshold. This moderately reduces the probability of the bear scenario where monthly revenue growth falls below 15% YoY. However, the valuation-driven concerns around margin dilution and elevated capex remain unchanged, so the overall rating and price targets are unchanged.