Measurement in retail media: Why getting it right matters more than ever
Opinion – Week in Focus
Retail media struggles with fragmented, self-reported measurement that is difficult to compare across platforms. It needs to change, as advertiser expectations are more sophisticated, says IAB Europe’s Marie-Clare Puffett.
Retail media has grown rapidly over the last five years, and yet the infrastructure needed to measure it properly has struggled to keep pace.
Advertisers are now allocating meaningful budgets to Retail Media Networks (RMNs) across Europe, drawn by the promise of first-party data and point-of-sale targeting that other channels simply cannot offer.
According to IAB Europe’s Attitudes to Retail Media Report 2025, these rank among the top reasons buy-side players are investing in the space. However, as spend has scaled, so has scrutiny, and the industry is increasingly confronting a question it can no longer defer: are we actually measuring retail media effectively?
The honest answer: not consistently. And that inconsistency is one of the bigger risks facing retail media’s continued growth.
The measurement problem isn’t new, but it is critical
Every maturing ad medium goes through a version of this reckoning. Search, display, and programmatic each went through periods where measurement was fragmented, self-reported, and difficult to compare across platforms. Retail media is in that phase now.
The difference is that the stakes are higher and advertisers’ expectations are more sophisticated. Brands entering retail media are not starting from scratch. They have established measurement frameworks elsewhere, and they expect retail media to meet a comparable standard.
What they often find instead is a patchwork. Metrics are defined differently from one RMN to the next. Attribution windows that vary without a clear justification. ROAS figures that may or may not account for returns, cancellations, or invalid traffic. Viewability reported against inconsistent baselines. For a brand managing spend across multiple networks, this makes meaningful comparison almost impossible, and it makes the channel harder to justify internally.
What good measurement looks like
The IAB Europe Commerce Media Measurement Standards, now in their second version, represent the industry’s most comprehensive attempt to address this. They cover the full measurement funnel, from media metrics like impressions, viewability, and video completion rate, through to attribution, customer insights, and incrementality, and they establish clear, consistent definitions across each area.
Some of what the standards define might seem straightforward, but the details matter.
Take the distinction between gross and net sales: gross recognises a sale at the point of payment, regardless of whether the item is returned; net deducts returns, cancellations, and refunds.
Anecdotal evidence suggests the delta between the two averages is around 20%. For a brand evaluating ROAS, that gap is not trivial. Without a clear standard on which figure is being reported, two networks can show very different results for campaigns of equivalent real-world performance.
The standards also address lookback windows, the period after an ad exposure during which a sale can be attributed to that ad. The recommended default is 30 days for post-view and post-click attribution, with flexibility for brands to adjust based on their product category.
An FMCG brand and a consumer electronics brand have fundamentally different purchase cycles, and measurement should reflect that. The standards also make specific provision for quick commerce, where the immediate nature of transactions calls for a shorter default window of seven days.
These may read as technical details. But they are the foundation on which advertisers’ trust is built or eroded.
Certification as the mechanism for adoption
Defining standards is one thing. Driving adoption is another. This is where IAB Europe’s Retail Media Certification Programme becomes relevant. Certification is the only mechanism that provides independent, third-party verification that an RMN or ad tech provider is actually adhering to the standards, not just claiming to.
For advertisers and agencies, certification offers something the standards document alone cannot: confidence. A certified network has been audited against specific compliance requirements by an accredited body. That changes the nature of the conversation between buyer and seller, and it changes what procurement and finance teams can reasonably expect when they ask how performance is being measured.
The programme is already gaining traction. Albert Heijn was the first certified network in Europe, and the pipeline is growing. As more networks achieve certification, it becomes increasingly difficult for those that haven’t to avoid the question of why.
The broader picture
European retail media ad spend stood at €7.4bn in 2021. By 2028, it’s forecasted to reach €28.8bn, nearly four times the size in under a decade. An area growing at that rate will attract increasing scrutiny from brands, agencies, and regulators alike. The networks that will hold their position as the market matures are those that can demonstrate measurement rigour, not just audience scale or data richness.
Standards and certification are not a constraint on that growth. They are a condition of it. An industry that cannot agree on how to define a sale or how long an attribution window should run will eventually find that advertisers route their budgets elsewhere that is more legible.
The work IAB Europe and its members are doing on measurement standards is, in that sense, foundational. Getting measurement right is not a technical exercise. It is the basis on which retail media earns its place as a trusted, permanent part of the media mix.
Marie-Clare Puffett is the senior director of industry development and marketing at IAB Europe