Arista's Revenue Growth Hits Its Fastest Pace Since Its IPO as AI Networking Demand Surges

Arista Networks reported third-quarter revenue growth on Tuesday at its fastest pace since its initial public offering, driven by demand for AI networking.

Arista Networks, Inc. (NYSE: ANET) is a Santa Clara, California networking company. It builds data-driven, client-to-cloud networking for large AI, data center, campus and routing environments. Its platforms run on EOS, its network operating system.

Sales beat the guide and estimates

Revenue was $3.66 billion for the quarter ended September 30, 2026. That was up 58.5% from a year earlier and 20.5% from the second quarter. Product revenue was $3.19 billion, and service revenue was $468 million.

The result cleared Arista's own guidance of about $3.3 billion for the quarter. By TickerGrove's calculation, revenue ran 10.8% above that guide. Arista had set the guide alongside its second-quarter results in August.

The consensus estimate for revenue was about $3.33 billion, as reported by Seeking Alpha and XTB. By TickerGrove's calculation, reported revenue beat that estimate by 9.8%.

Profit set records, and GAAP earnings topped adjusted earnings

GAAP net income was $1.56 billion, and GAAP diluted earnings per share were $1.22. GAAP means the standard accounting rules. A year earlier, GAAP earnings were $0.67 a share, on net income of $853 million.

Non-GAAP diluted earnings per share were $1.20, against the $1.08 consensus estimate. Non-GAAP means adjusted figures, excluding stock-based pay and similar items. By TickerGrove's calculation, the adjusted earnings beat was 11.1%.

Unusually, GAAP earnings topped the adjusted figure this quarter. The adjusted figure excludes a $134.5 million gain on strategic investments. Excluding a gain lowers adjusted profit, so the usual ordering flipped.

Gross margin slipped even as operating margin rose

GAAP gross margin was 63.6%, down from 64.6% a year earlier. Gross margin is the share of revenue left after production costs. GAAP gross profit was $2.33 billion.

The non-GAAP gross margin was 64.0%, down from 65.2% a year earlier. Operating margin moved the other way, helped by scale.

GAAP operating margin was 44.9%, up from 42.4% a year earlier. Non-GAAP operating margin was 49.1%, up from 48.6%. Operating income was $1.64 billion on a GAAP basis and $1.80 billion adjusted.

Executives called it a momentous quarter

"Arista registered another momentous quarter with the highest year-over-year revenue growth since our IPO and record profitability, surpassing even my high expectations," said Jayshree Ullal, chairperson and chief executive.

Ullal said the momentum highlights Arista's relevance for the generative and agentic AI era.

"This quarter brought a true trifecta for our company, setting new record highs in revenue growth, net income, and EPS," said Chantelle Breithaupt, chief financial officer.

Arista also launched open Ethernet rack-scale architectures with partners including AMD, Broadcom, Meta and Microsoft. Its Etherlink SU-144 design supports up to 144 accelerators in one rack. It can scale to more than one thousand XPUs across racks.

Arista was added to the S&P 100 in September 2026. The release describes that index as 100 major blue-chip companies.

Shares jumped after hours on the report

Shares rose 12.71% in after-hours trading to $191.47 as of 5:32 p.m. ET on Tuesday, according to Nasdaq quote data. The official regular close was $169.88, up 3.50% on the day. That reaction figure is an after-hours snapshot, not a close.

Arista had closed Monday at $164.14, the prior close. It rose in Tuesday's regular session before the report. The after-hours move extends that gain, on this one snapshot.

Cash and inventories both climbed

Net cash provided by operations was $3.98 billion in the first nine months of 2026. That is a nine-month figure, not a single-quarter result. A year earlier, the nine-month figure was $3.11 billion.

Cash and cash equivalents were $2.29 billion at September 30, 2026. Marketable securities were $12.07 billion at the same date. Together they totaled $14.36 billion, by TickerGrove's calculation.

Inventories were $3.21 billion, up from $2.25 billion at December 31, 2025. The build came as revenue scaled sharply through the year. Deferred revenue due within a year was $5.10 billion.

Fourth-quarter guidance is announced, not reported

For the fourth quarter of 2026, Arista said it expects revenue of $3.9 billion to $4.0 billion. That outlook is announced, not reported. Announced non-GAAP operating margin guidance is 48% to 49%.

Announced non-GAAP diluted earnings guidance is $1.26 to $1.30 a share. The release gives no fourth-quarter GAAP outlook range. It says a forward-looking GAAP reconciliation is not available without unreasonable effort.

By TickerGrove's calculation, the outlook midpoint implies sequential revenue growth of about 8.0%. The range itself implies about 6.6% to 9.4%, by the same calculation. That is slower than the third quarter's 20.5% sequential gain, off a larger base.

What remains unknown

What remains unknown includes whether the after-hours gain holds into Wednesday's regular session. After-hours snapshots can fade or reverse. The official test is the next regular close.

Fourth-quarter results also remain unknown, against the announced outlook. Whether large AI customers keep buying at this pace is unproven. The release gives no revenue split by customer.

What to watch next

What to watch next is fourth-quarter revenue against the announced $3.9 billion to $4.0 billion range. Watch non-GAAP operating margin against the announced 48% to 49% range. Watch diluted earnings against the announced $1.26 to $1.30 range.

Watch gross margin for a second year-over-year slip, or a recovery. Watch inventories after the build to $3.21 billion. Watch the next regular close against the after-hours snapshot.