STMicroelectronics (STM) Q3 2026: Gross Margin Hits 37%, Auto Up Only 5%

STMicroelectronics (STM) Q3 2026 gross margin reached 37.3%, in line with company guidance, but the recovery came mainly from industrial and data center demand while automotive grew more slowly than the company had planned. The company reported results for the third quarter ended September 26, 2026 in a results press release and on its earnings call on October 29, 2026 [1][2].

Three questions framed this quarter: whether an automotive recovery could fill STMicroelectronics' fabs and lift gross margin to about 37%; whether industrial microcontroller growth reflected real end demand; and whether data center growth would turn into profit and cash. Gross margin came in at 37.3%, profit and cash from the industrial and data center businesses were better than the prior baseline, and automotive revenue rose only 5% year over year [1][2]. Taken together, profit conversion is strengthening and the growth engine has shifted toward industrial and digital infrastructure. The roughly 39% fourth-quarter gross margin and an automotive acceleration remain management expectations, and a structural gross margin gain of more than 4 percentage points is not expected before the end of 2027 at the earliest [2].

STMicroelectronics is a Netherlands-headquartered, vertically integrated semiconductor manufacturer. It sells analog chips, sensors, power devices, microcontrollers and optical communication chips into four end markets: automotive, industrial, personal electronics, and communications equipment and computer peripherals [3]. In the third quarter, 68% of revenue went directly to equipment makers (OEMs) and 32% was sold through distributors [1]. Unused capacity charges, which arise when fabs run below capacity, weigh directly on gross margin [1][2].

Change one: gross margin back to 37.3%, but automotive did not keep pace

Third-quarter gross margin met the roughly 37% guidance, while automotive growth fell short of the company's July plan. Revenue was $3.757 billion, up 17.9% year over year. GAAP gross margin was 37.3%, 2.5 percentage points above the second quarter's 34.8% and 4.1 points above the year-ago quarter [1]. The company attributed the improvement to lower unused capacity charges and better product mix; those charges fell from $37 million in the second quarter to $23 million [1]. Automotive revenue was flat sequentially and up only 5% year over year, below the low-double-digit growth for the second half that management described in July [2][4].

The recovery in fab loading came mainly from markets other than automotive. Industrial revenue rose 40% year over year in the third quarter, and communications equipment and computer peripherals revenue rose 64%, which the company attributed to AI data centers and low Earth orbit satellite communications [2]. The power and discrete segment posted revenue of $477 million, up 11.3% year over year. It lost $81 million, and its operating margin improved from -21.4% in the second quarter to -17.1%, still worse than -15.6% a year earlier [1]. The company did not break down the specific causes of the narrower loss.

Improvement in automotive and power devices remains a management expectation for now. Management expects 2026 automotive growth slightly above 10% and fourth-quarter power and discrete growth well above 20% year over year, driven mainly by European electric vehicles [2]. The company guided fourth-quarter gross margin to 39.0%, plus or minus 2 percentage points [1]. Management expects a structural improvement of more than 4 percentage points once four legacy fabs close and customer qualifications are complete, toward the end of 2027 or in early 2028 [2].

Progress: industrial and data center growth turned into profit and cash

Growth in the industrial and data center businesses is already showing up in segment profit and company cash flow. The embedded processing segment reported revenue of $1.212 billion, up 24.1% year over year, with a 23.1% operating margin. The RF and optical communications segment reported revenue of $504 million, up 46.2%, with a 26.2% operating margin [1]. Free cash flow was $351 million in the third quarter, with net capex of $643 million, up from $401 million a year earlier [1]. Management raised its 2026 data center revenue expectation to about $1.3 billion and expects 2027 to be well above double that level [2].

Industrial growth appears to come from end demand for now, though order quality still needs to be tested. Sales through distribution rose 38.8% year over year, while management said inventory in distribution kept falling and remained below its standard target, which indicates distributors are selling product faster than they buy it [1][2]. Industrial book-to-bill was well above 3 and the backlog exceeds $20 billion. With lead times lengthening and prices rising on some products, the risk of duplicate customer orders cannot be ruled out until supply eases [2].

Conclusion

The Q3 2026 report changes the view of where STMicroelectronics' margin recovery is coming from. Industrial and digital infrastructure are driving growth and fab loading, and higher segment margins plus positive free cash flow show that profit conversion and cash generation are strengthening [1]. Automotive and power devices remain the weak spots, and the power segment is still losing money. The next tests are whether fourth-quarter gross margin reaches about 39%, whether power devices accelerate, and whether about $1.3 billion of data center revenue materializes. The company will adjust its reportable segments from January 2027, which may affect comparisons of segment data over time [2].

Sources

[1] STM Q3 2026 results 6-K filed 2026-10-29 (2026-10-29; Form 6-K third-quarter results press release; https://www.sec.gov/Archives/edgar/data/932787/000093278726000086/c3419c-q326earningspressre.htm) [2] STM Q3 2026 earnings call 2026-10-29 (2026-10-29; earnings call) [3] STM 20-F filed 2026-02-26 (2026-02-26; Form 20-F annual report; https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=0000932787&type=20-F&dateb=&owner=include&count=40) [4] STM Q2 2026 earnings call 2026-07-23 · segment and end-market performance (2026-07-23; earnings call; https://gateway.drillr.ai/mcp/private)