Taiwan Semiconductor Manufacturing Co. (2330) reported September 2026 revenue of NT$511.9 billion, according to its monthly filing with the Taiwan Stock Exchange. The figure was down a marginal 0.6% from August but up a striking 54.6% from September 2025. For the first nine months of the year, cumulative revenue is running 41.1% ahead of the same period last year.
Taiwan’s disclosure regime makes these numbers uniquely valuable: listed companies must report monthly revenue by the 10th of the following month, a cadence almost no other major market requires. That turns TSMC’s filing into the closest thing global investors have to an official monthly read on the semiconductor supply chain — weeks ahead of quarterly earnings anywhere else. It is worth stating the limitation plainly, though: this is companywide revenue with no segment or end-market breakdown, so it is an indirect indicator of demand, and attributing the growth to AI specifically is an inference rather than something the filing itself establishes.
TSMC: A Plateau, but at Extraordinary Altitude
The headline tension in September’s print is the contrast between the sequential and annual comparisons. A 0.6% dip from August is, on its own, unremarkable — monthly revenue at a foundry of TSMC’s scale moves with shipment timing and wafer mix. What matters is the level at which revenue has flattened: more than half a trillion New Taiwan dollars in a single month, 54.6% above where the company stood a year ago.
Two readings are consistent with the data. The bullish one is that TSMC is effectively running at the limits of what it can ship — a near-flat month at this altitude suggests output constrained by capacity rather than demand. The cautious one is that the sequential momentum that produced a 54.6% annual gain has, at least for one month, paused. The year-to-date figure argues against reading too much into a single flat month: a 41.1% cumulative gain over nine months is not the profile of a demand cycle that is rolling over. September’s year-over-year growth running above the year-to-date pace also indicates that recent months have been stronger than the early part of the year, not weaker.
Either way, the monthly cadence means the market will not have to wait long for the tiebreaker: October’s figure is due by November 10.
The Rest of the Tape: Foxconn Surges, MediaTek Lags
The other bellwether filings show a supply chain that is strong but far from uniform.
| Company (Ticker) | Sept. 2026 Revenue | MoM | YoY | YTD Cumulative YoY |
|---|---|---|---|---|
| TSMC (2330) | NT$511.9B | -0.6% | +54.6% | +41.1% |
| Hon Hai / Foxconn (2317) | NT$1,158.6B | +25.7% | +38.4% | +39.5% |
| UMC (2303) | NT$25.4B | +1.2% | +27.2% | +16.1% |
| MediaTek (2454) | NT$55.4B | -13.7% | +2.0% | +5.3% |
Hon Hai (Foxconn) posted the month’s most dramatic sequential move, with revenue jumping 25.7% from August to NT$1,158.6 billion — up 38.4% year-over-year. September typically marks the ramp of new consumer devices and server builds at the world’s largest contract assembler, and the fact that the year-to-date gain of 39.5% essentially matches the monthly year-over-year figure suggests this strength has been sustained all year rather than concentrated in a seasonal spike.
UMC, the mature-node foundry, grew a modest 1.2% month-over-month to NT$25.4 billion but is up 27.2% from a year ago. Notably, that annual pace is well above its 16.1% year-to-date cumulative growth — arithmetic that implies the mature-node business has been accelerating through recent months after a slower start to the year.
MediaTek is the outlier. The chip designer’s revenue fell 13.7% from August and grew just 2.0% year-over-year, with cumulative growth of 5.3% for the year. The gap between MediaTek’s near-flat annual growth and TSMC’s 54.6% surge shows clearly that the current cycle is concentrated in some parts of the ecosystem and not others. One plausible interpretation is that demand is flowing through leading-edge foundry and system assembly far more powerfully than through smartphone-centric chip design — with AI-related silicon the obvious candidate driver — but confirming that would require segment or end-market disclosure that these companywide revenue filings do not contain.
What to Watch
- TSMC’s October print (due by November 10). A second flat-to-down month would sharpen the capacity-ceiling-versus-demand-pause debate; a return to sequential growth would support the capacity-constrained interpretation. With 54.6% year-over-year growth in hand, even a flat October would leave the annual comparison formidable.
- The foundry–designer divergence. TSMC at +54.6% year-over-year versus MediaTek at +2.0% is a 50-plus-point spread within the same ecosystem. Whether MediaTek’s monthly figures begin to close that gap will indicate how broadly the demand cycle is spreading — and would offer indirect evidence on whether the divergence reflects an AI-centric demand mix, a question the monthly filings alone cannot answer.
- UMC’s acceleration. September’s 27.2% annual growth running far ahead of the 16.1% year-to-date pace points to a strengthening mature-node business. Subsequent monthly filings will show whether that trajectory holds.
All figures are drawn from official TWSE monthly revenue filings for September 2026. This article is for informational purposes only and does not constitute investment advice.
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.