Biggest-Mover: Amazon Amazon exhibited the most extreme shifts across the tracked periods. In Q4 2025, Amazon remained highly volatile, following the Q3 drop and recover. In Q4 Amazon dropped to ~25% in early November before surging to a peak of ~42% in early December.
Temu Temu capitalized on Amazon’s Q3 brief absence, peaking at ~27% impression share in July/August. However, in Q4 2025, Temu experienced a QoQ decline, dropping from ~24% in October to a low of ~16% in late November, before stabilizing near 17-22% in December.
eBay & AliExpress Both platforms remained stable with minimal QoQ variance. eBay hovered consistently between 17% and 19% throughout both quarters. AliExpress fluctuated slightly between 15% and 20%, reaching a minor Q4 peak of ~20% in November.
Biggest Mover: Shopping Shopping exhibited the most significant negative shift in absolute costs Quarter-over-Quarter. During Q3 2025 (July–September), Shopping CPC remained relatively flat at approximately €0.29–€0.30. However, in Q4 2025, it experienced a sharp, unfavorable spike, jumping to roughly €0.34 in November and maintaining that elevated cost through December. Interestingly, despite this absolute QoQ cost increase, Shopping’s Year-over-Year (YoY) CPC inflation actually decelerated, dropping from ~16% in Q3 to ~13.5% in Q4.
Performance Max Performance Max showed mild QoQ volatility. In Q3, CPC fluctuated between €0.39 and €0.41. In Q4, it saw a brief negative spike to €0.42 in November before recovering back to €0.40 in December. Its YoY CPC growth rate showed a notable cooling trend, falling from ~10.5% in Q3 to ~7.5% in Q4.
Search Search remained the most stable and cost-efficient channel in terms of inflation. Absolute CPC hovered consistently around €0.40 throughout both Q3 and Q4 2025, showing almost no QoQ degradation. Furthermore, Search maintained the lowest YoY cost increases overall, with its YoY growth rate dipping slightly from ~3.5% in Q3 to ~3.0% in Q4.
Impressions (YoY Comparison) Q4 2025 saw steeper Year-over-Year (YoY) impression declines across all channels compared to Q3 2025.
Clicks (YoY Comparison) Despite the drop in impressions, click deficits slightly recovered for two channels in Q4 compared to Q3.
Biggest Mover Shopping is the clear Biggest-Mover, displaying the most significant negative shifts. While Search and Performance Max showed minor QoQ recoveries in click volume YoY, Shopping’s click deficit plummeted by 5.1 percentage points (from -1.5% to -6.6%). Concurrently, its impression deficit nearly doubled, dropping 7 percentage points QoQ to reach a severe -14.5% YoY. Despite a mid-November seasonal spike pushing the overall index to ~1.40 for impressions and ~1.35 for clicks, the underlying YoY channel data indicates substantial contraction, particularly in Shopping.
Q4 2025 vs. Q3 2025 Performance Trends
Biggest-Mover: Search Search experienced the most significant and surprising shifts, making it the Biggest-Mover. YoY conversion growth plummeted by roughly 17 percentage points, dropping from 22% in Q3 to just 5% in Q4.
Despite this massive deceleration in conversions, Search was the only channel to see an increase in YoY cost growth, shifting from -1.0% in Q3 to -0.5% in Q4. This inverse relationship—crashing conversion growth paired with rising relative costs—is a strong negative signal. It directly indicates rising CPC and deteriorating acquisition costs, highlighting a severe drop in Search efficiency compared to the immediately preceding quarter.
Biggest-Mover: Search CTR experienced the most significant and surprising shift, surging from roughly 13.5% at the end of Q3_2025 to a massive peak of over 16.5% in mid-Q4_2025 before settling near 15%.
CTR Trends (Q4 vs Q3): Across all campaign types, CTR improved QoQ. Shopping CTR rose from ~1.5% in Q3 to peak at ~1.8% in Q4. PMax CTR climbed steadily from ~1.3% to ~1.6%. By device, Mobile CTR maintained the highest rate, growing from ~2.0% to ~2.2%, while Computers rose from ~1.5% to ~1.8%.
Conversion Rate Trends (Q4 vs Q3): Q4 introduced sharp seasonal spikes in late November. PMax conversion rates jumped from ~3.5% in Q3 to nearly 5.0% in Q4. Shopping conversion rates similarly peaked at 4.5% (up from ~3.5% in Q3). Conversely, Search conversion rates stagnated between 4.5% and 5.5%, notably underperforming the previous year’s Q4 metrics.
By device, Mobile conversion rates saw a dramatic Q4 spike to ~5.5% (up from ~4.0% in Q3) before sharply declining in late December. Surprisingly, Computer conversion rates trended downward QoQ, dropping from a Q3 average of ~5.5% to ~4.5% throughout Q4.
Median ROAS In Q3 2025, ROAS remained relatively stable, fluctuating between a low of 5.1 (early August) and a peak of 6.2 (mid-July). Moving into Q4 2025, ROAS exhibited extreme volatility. It initially dropped to 4.5 in mid-October before initiating a steep, sustained climb through November, ultimately peaking at a yearly high of 7.0 in mid-December.
Average Order Value (AOV) Q3 AOV saw a steady climb from roughly 70 in early August to a peak of 85 in early September. In Q4, AOV started stronger, hitting 90 in October. However, unlike the late-quarter surge seen in ROAS, Q4 AOV trended downward in November, hitting a low of 75 before recovering slightly to the 80–85 range in December.
Biggest-Mover ROAS is the definitive Biggest-Mover. The dramatic swing from a Q4 low of 4.5 to a peak of 7.0 represents a massive ~55% intra-quarter increase, significantly outpacing Q3’s constrained 5.1–6.2 range. The initial October ROAS dip to 4.5 points to a brief period of severe inefficiency—likely driven by rising CPCs, a strong negative signal—but the subsequent December surge marks the most significant and surprising positive shift in the dataset.