STMicroelectronics (STM) Q4 2025 earnings review
Revenue Inflects, But Profitability Crisis Deepens
STMicroelectronics delivered Q4 net revenues of $3.33 billion (+0.2% YoY), marking the first period of year-over-year growth after four quarters of decline, confirming the cyclical bottom has passed. However, the profitability picture remains severely stressed. GAAP Net Income reversed to a loss of $30 million, dragged down by $141 million in impairment/restructuring charges and $163 million in one-time tax expenses. Non-GAAP Operating Income fell 27.8% YoY. The critical Power & Discrete (P&D) segment collapsed to a $124 million operating loss, overshadowing strong growth in Personal Electronics and Imaging.
🐂 Bull Case
The company returned to year-over-year revenue growth in Q4 and expects sequential revenue decline in Q1 2026 (-8.7%) to be better than typical seasonality, confirming the end markets have passed the trough.
RF & Optical Communications (RF&OC) revenue surged 22.9% YoY, driven by strong engagement with key customer programs (likely Personal Electronics), providing an important offset to Industrial and Automotive weakness.
The long-term manufacturing transition to 300mm silicon and 200mm SiC is accelerating, with CapEx guided up 12-23% in FY26, suggesting management is investing through the trough to secure long-term cost benefits.
🐻 Bear Case
The P&D segment, critical for SiC growth, reported a catastrophic $124 million operating loss in Q4 2025, confirming significant volume and pricing challenges and raising severe concerns about near-term SiC profitability.
Q1 2026 Gross Margin is guided down to 33.7%, weighed by 220 basis points of unused capacity charges and the step-down loss of high-margin capacity reservation fees from automotive customers.
Despite returning to revenue growth, Adjusted Operating Income still declined 27.8% YoY, indicating negative operating leverage and a significant time lag before volume recovery translates to earnings.
⚖️ Verdict: 🔴
Cautiously Bearish. While the cyclical bottom is clearly past and volume is returning, the steep collapse in profitability—especially the $124M P&D loss—demonstrates that margin recovery is structurally challenged by high utilization costs and lost capacity fees. The stock price recovery will likely be delayed until tangible margin improvement materializes in H2 2026.
Key Themes
Power & Discrete (P&D) Operating Loss Deepens
The P&D segment remains the weakest link. Revenue declined steeply by 31.6% YoY, and the segment recorded a major operating loss of $124 million in Q4, worsening sequentially (Q3 loss was $67M). This outcome is driven by severely reduced volumes, particularly for SiC, and negative pricing pressure. The massive loss confirms that the SiC 'transition year' in FY25 was far worse for profitability than anticipated.
Sharp One-Time Charges Result in GAAP Loss
Q4 GAAP net income reversed to a $30 million loss, despite the sequential revenue increase. This was directly caused by two major non-recurring items: a $141 million pre-tax charge related to the manufacturing reshaping program (impairment, restructuring) and $163 million in one-time, non-cash income tax expenses. These charges highlight the painful cost of the ongoing structural transformation.
Q1 2026 Margin Outlook Deteriorates
Gross Margin is guided down sequentially to 33.7% in Q1 2026. This margin compression is due to continued high unused capacity charges (220 bps impact) and the previously flagged step-down reduction in high-margin capacity reservation fees, which fully expire at the end of FY25. This loss of high-margin 'intangible' revenue will be a sustained headwind throughout 2026.
RF & Optical Communications Leads Growth Acceleration
The MDRF Product Group drove Q4 growth, surging 7.0% YoY overall. RF&OC revenue accelerated dramatically, growing 22.9% YoY (versus a 3.4% decline in Q3), fueled by Personal Electronics customer programs. This segment achieved a strong 23.4% operating margin, providing necessary short-term profit stability.
Inventory Normalization Continues
Active inventory management is yielding results. Total inventory declined slightly sequentially ($3.17B to $3.14B), and Days Sales of Inventory (DSI) improved to 130 days from 135 days in Q3, nearing the 122 days seen in Q4 2024. This signals the company is successfully reducing excess buffer stock and aligning production with end demand, setting up the Industrial segment for further recovery in H1 2026.
Committed to Long-Term Structural Investment
Despite near-term softness, management increased its FY26 Net Capex guidance to $2.0B - $2.2B (up 12-23% YoY). This renewed investment is dedicated to the long-term strategic plan of accelerating the transition to 300mm silicon and 200mm SiC manufacturing (e.g., Catania fab), underscoring confidence in the medium-term market opportunity.
Automotive Performance Below Expectations
The CEO noted that while Personal Electronics, CECP, and Industrial performed above expectations, Automotive was 'below expectations' in Q4, contributing to overall softness in the APMS product group (-4.6% YoY) and the severe P&D segment loss. This persistent weakness remains a major cyclical drag.
Other KPIs
Revenue declined from $13.27B in FY24 to $11.80B in FY25, confirming the severity of the cyclical downturn experienced through the first three quarters, before the Q4 turnaround.
Gross Margin compressed dramatically from 39.3% in FY24, reflecting the adverse effects of negative product mix, lower manufacturing efficiencies, and substantial unused capacity charges incurred during the year's production cuts.
A reduction from $2.53 billion in FY24, reflecting management’s decision to optimize and align investments with market conditions, particularly slowing the pace of silicon carbide capacity expansion due to weaker short-term demand.
OpEx rose sharply due to the $141 million impairment, restructuring charges, and phase-out costs related to the manufacturing reshaping program. Excluding these one-time items, OpEx shows ongoing cost discipline, supporting the OpEx savings goal for FY26.
Guidance
The guidance implies a sequential decline of 8.7% compared to Q4 $3.33B. This is an **Accelerating** sequential trend, as it is 'better than average past seasonality' (typically >-10% decline). This suggests improving underlying demand trends despite seasonality.
This represents a sequential decline of 150 basis points from Q4’s 35.2%. This **Reversing/Decelerating** margin trend is due to a step-down in capacity reservation fees and continued structural pressure from unused capacity charges (expected 220 bps impact).
This is an **Acceleration** in capital investment, up 12% to 23% compared to the $1.79B spent in FY25. This funding is dedicated to the structural manufacturing program (300mm/200mm SiC), confirming that long-term strategic execution overrides short-term cyclical caution.
Key Questions
Power & Discrete Loss Root Cause
The P&D segment reported a staggering $124M operating loss. Can management break down how much of this loss is attributable specifically to SiC volume/pricing versus traditional Power and Discrete products?
SiC Pricing and Revenue Rebound
Given the severe SiC softness, what level of revenue growth in the SiC sub-segment is embedded in the Q1 outlook, and what is the expected timeline for P&D profitability recovery?
Margin Offset Strategy for Lost Fees
With high-margin capacity reservation fees expiring, what margin contribution (in basis points) is expected from the manufacturing efficiency program in 2026 to offset this structural headwind?