Similarweb (SMWB) Q4 2025 earnings review
Growth Decelerates as Retention Metrics Slide
Similarweb missed its own goal of revenue acceleration in Q4, delivering 11% growth as large AI data deals failed to close in time. More concerning is the deterioration in core SaaS metrics: Net Retention Rate (NRR) for large customers dropped sharply to 103% from 112% a year ago, and overall NRR fell below the critical 100% threshold to 98%. While the company touts GenAI as a growth engine (now 11% of revenue) and maintains positive free cash flow, the FY26 guidance suggests further deceleration to ~10% growth. The narrative has shifted from 'acceleration' to 'transition,' raising questions about the durability of the core offering.
🐂 Bull Case
Revenue from Generative AI solutions and data licensing scaled to 11% of Q4 revenue, up from 8% at the start of the year. This validates the 'data for LLM training' thesis, even if deal timing is lumpy.
The company marked its ninth consecutive quarter of positive free cash flow ($1.0M in Q4). Management expects to remain FCF positive and profitable (Non-GAAP) throughout FY26.
🐻 Bear Case
Overall Net Retention Rate (NRR) fell to 98%, implying the existing customer base is shrinking in value. Even the strategic >$100k ARR cohort saw NRR compress to 103% (vs 112% last year), indicating upsell struggles or churn.
Despite a massive opportunity in AI, revenue growth is decelerating. After peaking at 17% in Q2, growth slowed to 11% in Q4, and FY26 guidance points to ~10%—hardly the profile of a high-growth AI data play.
⚖️ Verdict: 🔴
Bearish. The drop in NRR below 100% is a significant red flag for a SaaS business. Combined with decelerating revenue growth and reliance on 'lumpy' large deals that slipped out of the quarter, the risk profile has increased significantly despite the GenAI narrative.
Key Themes
Deteriorating Net Retention Rates
A critical weakening in customer stickiness and upsell power. The NRR for customers >$100k ARR, historically a strength, slid to 103% from 112% a year ago. Worse, overall NRR dropped to 98%. Management blames 'tough comps' from 2024 upsells and one-time nature of LLM trials, but sub-100% NRR suggests the core product is facing pressure or optimization from clients.
Deal Timing Volatility
Q4 revenue missed internal acceleration targets due to the timing of 'two large LLM data training contracts' that failed to close. This highlights the risk of the new strategy: shifting from steady SaaS revenue to lumpy, high-value data licensing deals introduces significant quarterly volatility and forecasting risk.
Shift to Multi-Year Commitments
A positive structural shift: 60% of ARR is now under multi-year subscriptions, up from 49% a year ago. This drove Remaining Performance Obligations (RPO) up 17% to $288.8M, outpacing revenue growth and providing some visibility cushion against the retention headwinds.
Generative AI Segment Growth
Revenue from GenAI data and solutions reached 11% of total revenue in Q4, up from 8% at the start of the year. The company launched 'Similarweb AI Studio' and partnered with 'Manus' to embed data into AI agents. This segment is growing, but currently insufficient to offset the deceleration in the core business.
Upmarket Customer Acquisition
Despite retention issues, the company continues to land larger clients. Customers with >$100k ARR grew 12% YoY to 454. This cohort now represents 63% of total ARR, up from 61% last year, confirming the strategy to move upmarket is working on the acquisition front, even if expansion is lagging.
Other KPIs
Decelerating. Growth slowed to 11% YoY from 16% in the prior year period and 17% in Q2. Management cited 'longer sales cycles' for large AI opportunities.
Stable. Improved slightly from 4% a year ago. The company is balancing investments in an AI-specialized sales force with disciplined cost management. FY26 guidance implies margins remaining in the ~5-6% range.
Positive but declining. Down from $2.7M in 24Q4. For the full year, FCF was $13.0M vs $27.4M in FY24, reflecting higher CapEx and working capital timing.
Guidance
Decelerating. Implies ~9% YoY growth at the midpoint, down from 11% in Q4 and 14% in 25Q1. Reflects the continued drag from longer sales cycles.
Decelerating. Midpoint implies ~10% growth, down from 13% in FY25. This contradicts the 'reacceleration' narrative pitched earlier in the year.
Accelerating profitability. Implies a margin of ~5.6% at midpoint, up from 3.2% in FY25 ($9.1M). Management is prioritizing margin expansion amidst slower top-line growth.
Key Questions
Structural vs. Cyclical NRR Decline
With overall NRR dropping below 100% (98%) and large customer NRR falling 900bps in a year, is this solely due to 'tough comps' and one-time deals, or are core Web Intelligence customers churning/optimizing spend?
Visibility on Large Deal Closures
Two large LLM deals slipped out of Q4. What is the specific confidence level that these will close in Q1, and are they factored into the Q1 guidance of only 9% growth?
Sales Force Productivity
After significant investments in upskilling the sales force for the 'AI world,' why is the top-line guidance decelerating to 10% for FY26? When will these GTM investments yield tangible revenue acceleration?