Calix (CALX) Q3 2026 earnings review
Calix software growth speeds up, but memory costs squeeze profit
Calix, which sells network hardware and cloud software to internet providers, saw software growth speed up while memory chip costs squeezed hardware profits. Total revenue rose 14% to $302 million, landing near the bottom of the company's plan, while software and service sales jumped 19% and hit a record gross margin. Chief executive Michael Weening kept the full-year revenue outlook near 19% growth, and by our math the fourth-quarter plan leaves gross margin flat at 53.5%.
| Revenue | $301.7M +14% from a year ago |
|---|---|
| Software and service revenue | $51.9M +19% from a year ago |
| Gross margin, excluding one-offs | 53.5% -4.2 percentage points from a year ago |
| Full-year revenue outlook | Unchanged ~19% growth (upper end of 15–20%) |
⚖️ Verdict: ⚪ Neutral
The story is unchanged because the rebound in software offset ongoing hardware cost pressure without breaking the backlog logjam. Software revenue and margins improved after all customers moved onto the Calix One AI platform, and internal AI tools let management plan for flat engineering spend next year. The bad news: multi-year contracted backlog grew only 13% before an accounting change despite signed AI contracts doubling, and buybacks plus inventory builds have drained 60% of the cash pile this year.
The question now is whether the new AI platform will drive faster multi-year contract growth or mainly help existing customers add subscribers at the current pace. If the new contracts carry real spending, contracted backlog growth will climb toward the 19% software pace; if they are mostly bundled upgrades, backlog growth will stay in the low teens. Fourth-quarter backlog and software revenue will test both sides.
🐂 Bull Case
Software Growth and Margins Rebounded on Calix One
"The third quarter marked our shift from AI enablement to AI execution," chief executive Michael Weening wrote. Calix sells network boxes and cloud software to internet providers, and it moved all of its cloud customers onto its new AI platform, Calix One, in March. After slowing for three straight quarters, software and service revenue grew 19.5% from a year ago to $51.9 million.
The division's gross margin, excluding one-offs, reached a record 67.2%, up 2.0 percentage points from a year ago and 3.4 points from last quarter. That beat the prior 66.5% record because the broadband supplier finished moving customers off its old cloud system and added more subscribers. Customers also published concrete savings from the tools, with rural provider Chariton Valley cutting operating costs by nearly $500,000 this year.
What to watch: software and service revenue growth in the fourth quarter. A second quarter near 20% growth would show that the new platform is driving lasting software demand rather than a one-quarter bounce.
AI Tools Let Calix Hold Engineering Spend Flat
Calix is using AI tools from its partners inside its own business to keep overhead down while revenue grows. Operating expenses, excluding one-offs, fell to 41.1% of revenue from 43.2% a year ago, a drop of 2.1 percentage points. Sales and marketing costs shrank by 1.6 points of revenue, and general and administrative overhead fell by 1.1 points, while research and development rose 0.6 points.
Weening wrote that an engineering team finished a 15-month project in three months using the new tools. Because of those gains, the company plans to "deliver more capabilities to customers in 2027 than in 2025 and 2026 combined, with R&D investment flat to down from 2026". Holding engineering spend flat while revenue grows would move the business closer to its 20% operating margin goal.
What to watch: first-quarter 2027 operating expense outlook when fourth-quarter results arrive. It will show whether research and development spending actually stops growing after the fourth-quarter customer conference costs pass.
🐻 Bear Case
Memory Costs Keep Squeezing Hardware Margins
Calix gets 83% of its revenue from network hardware appliances, and those boxes need memory chips. The company said "a rapid, industry-wide rise in memory costs due to the demand from the building of AI data centers" pushed appliance gross margin down 5.5 percentage points from a year ago to 50.7%. Cost of goods for appliances jumped 4.2 percentage points of total revenue.
- Total gross margin, excluding one-offs: 53.5%, down 4.2 percentage points from a year ago
- Fourth-quarter gross margin outlook: 52.25% to 54.75%, flat at the 53.5% middle of the range
- Full-year gross margin, by our math: down 2.6 percentage points from 2025, missing the Q1 plan for a 0.5 to 1.5 point drop
The San Jose group adds surcharges "intended to offset incremental memory costs over time" without adding a profit markup. Because those fees pass costs through at zero margin, they dilute the gross margin percentage even when they recover the dollars. The fourth-quarter outlook shows no margin recovery yet, confirming that higher chip prices outweigh the software margin gains.
What to watch: appliance gross margin in the fourth quarter. A drop below 50.7% would mean chip inflation is still outrunning the monthly surcharge resets.
Contracted Backlog Still Lags Behind AI Claims
Weening wrote that "Calix One contracts signed in the third quarter of 2026 more than doubled from the previous quarter". Management also predicted that remaining performance obligations (RPO) — the total value of signed multi-year software and service contracts not yet recognized as revenue — would grow faster as customers adopt AI workflows. Yet total RPO rose only 11.6% from a year ago to $395.7 million.
This quarter Calix began adding non-cancellable hardware orders to RPO, so it elected "to eliminate the value of RPOs for contracts with a duration of one year or less". That rule change removed $6.0 million of short software deals. Even adding that $6.0 million back, RPO grew 13.3% from a year ago by our math, adding $15.3 million in the quarter, which is barely above the 11.5% pace in the second quarter.
What to watch: fourth-quarter RPO growth on a comparable basis. Without a jump above 15%, doubling the number of AI contracts is not moving the total value of multi-year commitments.
Buybacks and Inventory Drained Over Half the Cash
Calix has prioritized buying stock and stockpiling hardware parts over holding cash on its balance sheet. Cash and marketable securities fell to $154.8 million from $388.1 million at the end of December, a 60% drop in nine months. The company spent $50.0 million buying back 1.4 million shares this quarter, bringing nine-month buybacks to $290.2 million, and the board added $100 million to the buyback plan in October.
At the same time, the hardware maker added $14.6 million of inventory in the quarter to guard against supply shortages, lifting total inventory 74% from a year ago to $187.9 million. That inventory build held third-quarter free cash flow to $3.4 million, down 87% from $26.7 million a year ago. With only $37.4 million of operating cash flow in nine months, selling investments funded the buybacks.
What to watch: inventory levels and free cash flow in the fourth quarter. Another inventory build alongside heavy buybacks would pull cash and investments closer to $100 million.
Risks this quarter didn't answer
Several standing risks and growth drivers received no quantitative update or only a brief mention in the stockholder letter.
- Customer concentration and international sales: one unnamed customer accounted for 11% of revenue (after 12% last quarter), while international revenue fell 14% from a year ago to 5% of the total.
- Federal broadband funding (BEAD): listed only as a forward-looking factor, with no order or shipment figures to show when government-funded builds will lift revenue.
- Large service provider wins: mentioned as a target market for software on open gateways, with no named Tier-1 contracts disclosed.
- Satellite competition and May 2026 memory-supply lawsuit: neither appeared in the stockholder letter; the quarterly filing will carry the legal update.
💲 Other KPIs
Appliance revenue — sales of network boxes and optical gear — reached a record $249.8 million, up 12.5% from a year ago and 2.9% from last quarter. Growth slowed from 22.5% in the second quarter and 29.5% in the first quarter as the company lapped last year's 32% revenue jump.
The diluted share count fell 7.7% from 69.8 million a year ago after the company bought back 6.3 million shares in the first nine months of 2026. The lower share count kept profit per share excluding one-offs flat at $0.44 even though net income excluding one-offs fell 6.8% to $28.5 million.
Days payable outstanding — the average time Calix takes to pay its suppliers — fell to 44 days from 54 last quarter, but remains well above 18 days a year ago and its 25-to-35-day target. Paying bills more slowly helped keep operating cash flow positive while inventory turns sat at 2.8, below the 3-to-4 target.
🔮 Guidance
New. The plan calls for revenue to rise 4.1% from this quarter and 15.3% from a year ago at the $314 million middle of the range. That sits inside the $313 million to $323 million range implied by last quarter's full-year target, and includes zero-margin surcharges for memory costs.
Unchanged. Management now pegs full-year growth at about 19%, matching the 18.9% growth implied by the fourth-quarter outlook by our math. That confirms the prior target of the upper end of 15% to 20% after a 20% year in 2025.
New. The 53.5% middle of the range matches the third quarter and sits 4.5 percentage points below a year ago. Management expects memory costs to keep rising, with customer surcharges offsetting a larger share of the cost increase than in the third quarter.
New. Planned spending rises 5.3% from this quarter and 2.9% from a year ago at the $130.5 million middle of the range. The step-up pays for the annual ConneXions customer conference and five extra calendar days in the fourth quarter.
New. At the $0.45 middle of the range, profit per share rises 2.3% from this quarter and 15.4% from $0.39 a year ago. The plan assumes 63.4 million diluted shares, down another 1.0 million from the third quarter on continued buybacks.
Unchanged. The full-year tax rate plan stays at 23% to 25% for a fifth straight quarter.
❓ Key Questions
How much did memory surcharges add to third-quarter revenue?
Calix charges fees to recover memory costs at zero profit margin. Without the dollar amount, investors cannot tell how much of the 14% revenue growth came from shipping more gear versus passing through higher chip costs.
How much of the contracted backlog is now hardware?
Non-cancellable hardware orders over one year entered RPO this quarter under the supply assurance program, while $6 million of short software deals left. Management did not disclose the dollar amount of hardware added to the $395.7 million total.
How many customers signed Calix One contracts in Q3?
Management said signed Calix One contracts more than doubled from the second quarter, after tripling the quarter before, but gave no base number or dollar value to explain why total RPO growth stayed near 13%.
Will Calix borrow money if buybacks keep draining cash?
Cash and securities dropped by $233 million in nine months to $154.8 million while the board added $100 million to the buyback plan, leaving $144 million authorized against $3.4 million of quarterly free cash flow.