# Fortinet Stock Q3 2026: Billings, Service Revenue and the Share Price Drop
> Fortinet stock Q3 2026: revenue rose 20.5% to $2.08bn and billings 29.2%, but it cut its service revenue outlook and FTNT fell 20%. Earnings and outlook.

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## Facts
- Ticker: FTNT
- QSILabs fair value: $52.89 USD
- Price: $126.21 (as of 2026-11-02)
- As of: Q3 2026 results (quarter ended 2026-09-30, reported 2026-10-28) and Form 10-Q dated 2026-10-29; price as of 2026-11-02 close
- Fiscal period: Q3 2026 (July-September 2026)
- Published: 2026-11-02
- Updated: 2026-11-02
- Author: QSI Labs Research
- Canonical: https://www.quantitativesuperintelligencelabs.com/research/fortinet-stock-q3-2026-earnings-billings-service-revenue/

## Short answer
Fortinet stock Q3 2026 comes down to a quarter that beat on almost every line but disappointed on the one investors watch most closely, service revenue. In the three months to 30 September 2026 revenue rose 20.5% to $2.08bn, product revenue 36.8% to $765m and billings 29.2% to $2.34bn. Service revenue grew 12.7% to $1.31bn, and Fortinet cut its 2026 service revenue outlook to $5.15bn to $5.17bn from $5.18bn to $5.22bn. GAAP operating income rose 28.7% to $704m, a 33.9% margin, and free cash flow was $865m. The shares fell 20.1% the next day and closed at $126.21 on 2 November 2026, 27.5% below their pre-results close. Our discounted cash flow model values the shares at $52.89, well under half the price; below we show which assumptions drive that gap and how far each one moves it.

## Key takeaways
- Revenue and billings beat. Revenue rose 20.5% to $2,078.4m and billings, revenue plus the change in deferred revenue, rose 29.2% to $2,336.3m. Fortinet raised its 2026 revenue outlook to $8.125bn to $8.215bn, about 20% growth.
- Service revenue lagged. Service revenue, mostly security subscriptions and support, grew 12.7% to $1,313.4m. Fortinet lowered its 2026 service revenue range to $5.15bn to $5.17bn, which it said was a timing issue caused by large deals with services that start in stages.
- Product growth slowed from the first half. Product revenue, mainly FortiGate firewalls, rose 36.8% to $765.0m. Investors had expected growth of about 50%, according to a Yahoo Finance report.
- Margins rose. GAAP operating margin rose to 33.9% from 31.7%, and the non-GAAP operating margin to 38.2%, which chief financial officer Christiane Ohlgart called "a third quarter record".
- Cash flow is strong. Free cash flow rose 52.4% to $864.8m and was $2.84bn in the first nine months. Fortinet ended September with $5.32bn of cash and investments and $497m of debt.
- The shares gave back much of their 2026 rally. FTNT closed at $194.75 on 9 October and $126.21 on 2 November, still 58.9% above the end of 2025.
- QSILabs value: $52.89 a share, against a $126.21 close on 2 November 2026. A two-stage cross-check gives $54.05; analysts' average target is $145.96 and their lowest $110.
- What to watch. Whether service revenue growth picks up in 2027 as Fortinet expects, how product sales hold up against a strong 2026, component costs and lead times, and the take-up of new AI security and SASE services.

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