TSMC stock: a 0.6% sales dip masks a NT$1.49T quarter

TSMC stock heads toward its October 15 earnings call with a stronger sales base than September’s small decline suggests. Taiwan Semiconductor Manufacturing Co. reported on October 8 that September revenue fell 0.6% from August to NT$511.86 billion. Compared with September last year, however, sales rose 54.6%.

The bigger finding is in the quarter. Adding the company’s July, August and September reports gives NT$1.494 trillion in third-quarter revenue, up 17.6% from the second quarter, TECHi calculates. A slight retreat from August therefore leaves TSMC with a substantially larger business to turn into profit. The monthly release does not yet tell investors how much of that growth reaches earnings.

The New York-listed ADR ended Friday, October 9, at US$453.31, down 1.02% from the previous close, according to TECHi’s TSM quote, supplied by Yahoo Finance. That is the regular-session close at 4 p.m. EDT, with the provider’s delay interval unspecified—not a Sunday trading price. The move alone does not identify why shareholders sold.

The quarter matters more than one monthly dip

TSMC’s monthly revenue series shows sales rising sharply between July and August, then holding near that higher level in September. The third-quarter total exceeds the sum of April through June by NT$223.86 billion. These are consolidated sales in New Taiwan dollars; the monthly figures are unaudited.

The sales behind TSMC’s third quarter

Period, 2026	Revenue, NT$ billion	Basis
July	467.580	Monthly disclosure
August	514.806	Monthly disclosure
September	511.857	Monthly disclosure
Q3 total	1,494.243	TECHi sum of July–September
Q2 total	1,270.381	TECHi sum of April–June

That distinction changes how the September decline should be read. It is a comparison with a particularly strong August, rather than evidence that the whole quarter contracted. It also cannot establish whether AI customers, smartphone launches, pricing or currency movements supplied the incremental sales: the monthly release does not break them out.

There is a calendar wrinkle, too. September has 30 days and August 31. Dividing each month’s revenue by its calendar days gives NT$17.06 billion for September versus NT$16.61 billion for August, a 2.7% increase. That is a simple normalization, not a measure of daily factory output, orders or customer demand; invoicing and revenue recognition need not happen evenly. It shows why a 0.6% monthly decline alone is a weak basis for declaring a slowdown.

Why NT$1.49 trillion is not yet a reported dollar revenue beat

TSMC’s third-quarter guidance is stated in U.S. dollars: US$44.6 billion to US$45.8 billion. The same guidance page lists an exchange-rate assumption of NT$32 per U.S. dollar.

At that assumed rate, the monthly sales total translates to about US$46.70 billion, roughly 2.0% above the top of the guidance range. This is TECHi’s constant-assumption calculation, not TSMC’s reported third-quarter U.S.-dollar revenue. The actual accounting translation can differ. Using today’s spot exchange rate would introduce another mismatch.

For readers following the October sales-and-earnings sequence, the new disclosure supplies the missing September figure. The remaining question is how the completed sales quarter converts into reported profitability.

Each margin point now represents almost NT$15 billion

TSMC’s July earnings presentation put second-quarter gross margin at 67.7% and guided to 65%–67% for the third quarter. Gross margin is the share of revenue left after the cost of producing the goods sold, before operating expenses and other items.

Applying that guidance range to the reconstructed NT$1.494 trillion sales total gives NT$971.3 billion to NT$1,001.1 billion in illustrative gross profit. A single percentage point is worth approximately NT$14.94 billion. These are sensitivity calculations using guidance, not an earnings forecast or a price target.

That is why the revenue release cannot settle the stock’s outlook by itself. Stronger sales can support more gross-profit dollars while a lower margin leaves less profit from each dollar of revenue. And gross profit is still several steps away from earnings per share or cash available after capital spending.

The optimistic interpretation is straightforward: TSMC has already disclosed a larger sales base, which gives it room to absorb some margin pressure. The counterargument is that investors may already expect that growth. A disappointing margin or a weaker outlook for the following quarter could matter more to the share price than another large revenue number.

The company schedules its earnings conference for October 15 at 2 p.m. Taiwan time, or 2 a.m. EDT. The figures to compare are the reported U.S.-dollar revenue, gross margin against the 65%–67% range, and the next quarter’s guidance. Together, they will show whether the sales expansion is translating into the profit growth shareholders are paying for.