Commerce media has a proof problem. In a new survey from SMG, the IAB and IAB UK, 46% of brand respondents said the thing that would convince them to raise investment is proven, measurable ROI and incremental sales impact. No other answer crossed 8%.
The fieldwork ran in July and August 2026 across 281 professionals: 168 brands and advertisers, 52 agencies and 61 retail and commerce media networks in the UK, US, Europe and Australia. What stands out is not that brands want more inventory. They want evidence that the ads created sales that would not have happened otherwise.
Reporting, not activation, is the bottleneck
When asked where commerce media is least connected, respondents pointed first at reporting (34%). Creative came next at 30%, consumer insights at 29% and planning and measurement at 28%. Activation barely registered at 17%.
Only 14% of respondents say multichannel campaigns are always planned from a single brief, and another 14% say they always get unified reporting across channels. That explains the lukewarm mood: 54% rate the ecosystem at 7 out of 10 or higher, but just 17% give it a 9 or 10.
Why this matters now
Retail media is scaling fast. IAB Europe put 2024 European retail media spend at €13.7 billion and forecasts €20.8 billion for 2026. UK online retail media hit £1.5 billion in H1 2025. As budgets spread across multiple retail networks, fragmented reports become more expensive to reconcile.
Previous research points the same way: Incremental estimated in June 2026 that siloed attribution misses 36% to 53% of total retail media impact because in-store and off-retailer sales sit outside single-retailer reporting.
What “proven ROI” actually demands
The report draws a sharp line between reported results and causal results. Strong reported ROAS can still be a number that would have happened anyway. That is why the IAB’s incrementality guidelines, released in November 2025, rank experiments above model-based counterfactuals and platform-reported lift.
The report puts it bluntly: “AI can automate coordination. It cannot automate alignment.” Brands are not primarily asking for more placements or lower prices. They are asking for proof.
A connected system to fix it
The authors propose a nine-step Connected Campaign System. The practical sequence for buying teams looks like this:
- Set one business objective and audience strategy before any channel plan.
- Run a single brief that assigns coordinated roles to each channel and retailer.
- Close with shared optimisation, unified measurement and a learning loop across retail networks.
The point is connection without standardisation. Each retailer can keep its own data and formats, but the campaign strategy should not get lost between dashboards.
What to do next
Before increasing a retail media budget, ask the network for an incrementality test — a holdout or experiment design — not just platform-reported lift. Push for one brief and unified reporting across retailers. And treat in-store media as part of the same test: 47% of respondents see an in-store channel as the greatest incremental value when connected, yet 41% call in-store the hardest channel to connect.
Source: PPC Land
