Fortinet (FTNT) Q4 2025 earnings review
Product Refresh Drives Acceleration, SASE Explodes
Fortinet closed FY25 with a decisive beat, validating the bull case for a hardware refresh cycle. Billings growth accelerated to 18% (up from 14% in Q3), and Product Revenue surged 20% as customers upgraded aging firewalls. Unified SASE was the standout star, accelerating to 40% growth (vs 19% last quarter). While FY26 guidance implies a mathematical deceleration (midpoint ~12%), the underlying momentum in Product and SASE suggests the 'Rule of 45' engine remains intact.
🐂 Bull Case
Product revenue growth accelerated to 20% YoY, a stark turnaround from the negative growth seen in early 2025 (-18% in Q1). This confirms the 2026/2027 firewall end-of-service refresh cycle is actively driving demand.
Unified SASE billings growth accelerated massively to 40% in Q4 (compared to 19% in Q3). Fortinet is successfully converting its massive firewall install base into recurring SASE revenue.
🐻 Bear Case
Service revenue growth (+12%) is significantly lagging Product growth (+20%). Since services are the higher-margin recurring tail, this lag creates a temporary drag on total revenue growth until the new hardware cohort attaches services.
Despite the Q4 beat, management guided FY26 revenue to ~12% growth (midpoint $7.6B). This implies a deceleration from Q4's 15% pace, suggesting caution regarding the macroeconomic environment or service revenue recognition timing.
⚖️ Verdict: 🟢🟢
Strong Buy. The hardware refresh thesis is validated by 20% product growth, and SASE acceleration (40%) proves the platform strategy works. Profitability is elite (37% margin). The conservative FY26 guide looks like a 'beat-and-raise' setup.
Key Themes
Unified SASE Breakout
Accelerating. Unified SASE billings grew 40% YoY, a massive jump from the 19% reported in Q3. This confirms Fortinet is winning the convergence war by leveraging its installed base. The 'Single OS' strategy is effectively displacing competitors.
Product Revenue Resurgence
Accelerating. Product revenue grew 20% YoY to $691M, continuing the recovery from -18% in Q1. This is the leading indicator for the business; strong hardware sales today create the installed base for high-margin service revenue tomorrow.
AI Factory Integration
New Strategic Driver. Fortinet announced an integrated solution with NVIDIA (BlueField-3 DPUs) to secure 'AI Factories.' While revenue contribution is currently small, this positions Fortinet's firewalls as essential infrastructure for the booming AI data center build-out.
Guidance Deceleration
Decelerating. FY26 revenue guidance of $7.50-$7.70B implies ~11.7% YoY growth at the midpoint. This is a step down from the 15% revenue growth achieved in 25Q4. It suggests management expects the 'Service Revenue Lag' to persist through 2026.
Service Revenue Drag
Stable/Lagging. Service revenue grew only 12% in Q4, acting as an anchor on the total top line. This is a known lag effect (services attach after hardware is deployed), but it dampens the immediate financial impact of the product boom.
Other KPIs
Stable/High. Margins remain elite, hovering near 37% (vs 39% a year ago). This demonstrates disciplined execution even while investing in SASE and AI growth initiatives. Guidance for FY26 is 33-36%, suggesting margins may compress slightly due to investment mix.
Accelerating. Full year FCF grew 18% YoY (from $1.88B in FY24). Strong cash generation supported a $1.0 billion expansion of the share repurchase program.
Accelerating. Beat the full-year guidance range of $7.325-$7.475B (provided in Q2). Growth of 16% for the full year confirms that demand remains resilient despite macro concerns.
Guidance
Decelerating. Implied growth is ~12.5% YoY (vs 15% in 25Q4). This reflects seasonality and the continued mix-shift drag from slower service revenue.
Decelerating. Midpoint ($1.82B) implies ~14% YoY growth, down from 18% in 25Q4 but consistent with 25Q1 growth of 14%. Likely conservative.
Decelerating. Midpoint growth of 11.8% is below the 14% achieved in FY25. This conservative outlook likely factors in the service revenue lag and macro uncertainties.
Stable. The midpoint (34.5%) is roughly in line with FY25 (35.5%), indicating the company intends to maintain its 'Rule of 45' profile while absorbing hardware COGS.
Key Questions
Service Revenue Catch-Up
With Product revenue growing 20%, when exactly do you expect Service revenue growth to trough and re-accelerate to match? Is 2H 2026 realistic?
Unified SASE Acceleration Sustainability
Unified SASE billings jumped to 40% growth in Q4. Was this driven by a few mega-deals, or is this a structural inflection point in the SD-WAN to SASE upgrade cycle?
Conservative Guidance Rationale
Your FY26 billing guidance implies deceleration to ~12.5%. Given the 18% exit velocity in Q4 and a hardware cycle tailwind, is this guidance assuming a macro deterioration?